Copyright: Copyright ® 1991-1995 SMI Corporation


Periodic Table Help Index

How To ...

Order Periodic Table

What is Shareware?

Get Information on an Element

Use the Table window

Use a Data window

Use a Decay Tree window

Change the Table Fonts

Change the Table Colors

Change the Decay Tree Colors

Change the Decay Tree Fonts

Change Options

Use the Legend

Use the Toolbar

Exit

Use the Dialogs

Commands

File menu

Edit menu

View menu

Period menu

Group menu

Tool menu

Option menu

Window menu

Help menu

Background

Periodic Law

Electron Shells

Subshells

Alkali Metal

Alkali Earth Metal

Metal

Transition Metal

Rare Earth

Non-Metal

Halogen

Noble Gas

Radioactive Decay

Isotopes

Half-Lives

Interactions

Subatomic Particles

Quantum Chromodynamics


How to Order Periodic Table
How to Order Periodic Table 3.0

Periodic Table 3.0 Order Form/Invoice (ACD).  Please send to:

SMI Corporation, P.O. Box 582221, Tulsa, OK 74158

Ordering by check:  You can order by sending a check and this order form to the address above. To print this order form, click on Print Topic in the File pull-down menu.  Alternately, you can print the ASCII text file ORDER.TXT (distributed with Periodic Table).

Credit card ordering:  You can order with MasterCard or Visa from SMI Corporation by calling (918) 241-2301 from 8:00 am to 5:00 pm central time Monday through Friday.  You can also mail credit card orders by filling out this order form and mailing it to the above address.

Site licenses:  Site licenses are available for Periodic Table.  Call (918) 241-2301 to find out about the details.

Periodic Table 3.0     Single User Lic.:___ @ $30.00 ea.= ___________

Shipped with printed manual and latest version on disk.

Disk size:  ___ 5.25  ___ 3.5

Oklahoma residents add 8% sales tax                     + ___________

Shipping and Handling charge                            + _____$3.50_

International (outside US or Canada) orders add:  $5.00 + ___________

                                           Total payment  ___________

Payments must be in US dollars drawn on a US bank or by MasterCard or Visa.

Prices are subject to change without notice.

            Name: __________________________________ Date: _________

         Company: __________________________________________________

         Address: __________________________________________________

                  __________________________________________________

City, State, Zip: _______________________________ Country: _________

       Day Phone: __________________ Evening Phone: ________________

Electronic mail address: ___________________________________________

For Credit Card orders:    ___ Visa        ___ MasterCard

    Card Number: ________________________________________

    Exp. Date: ___________________

    Signature: __________________________________________

Comments:


What is Shareware?

Also see ASP Ombudsman Statement

Shareware distribution gives users a chance to try software before buying it.  If you try a Shareware program and continue using it, you are expected to pay for the product.  Copyright laws apply to both Shareware and commercial software, and the copyright holder retains all rights, with a few specific exceptions stated below.

Shareware authors are accomplished programmers, just like commercial authors, and the programs are of comparable quality.  (In both cases, there are good ones and bad ones!)  The main difference is in the method of distribution.

The author specifically grants the right to copy and distribute the software, either to all and sundry or to a specific group.  Shareware is a distribution method, not a type of software.  The Shareware system makes fitting your needs easier, because you can try before you buy.  And because the overhead is low, prices are low also.  Shareware has the ultimate money-back guarantee -- if you don't use the product, you don't pay for it.

SMI Corporation is a member of the Association of Shareware Professionals (ASP).  As such all its programmers adhere to the high standards set out by the ASP.


Ombudsman Statement

This program was produced by a member of the Association of Shareware Professionals (ASP).  ASP wants to make sure that the shareware principle works for you.  If you are unable to resolve a shareware-related problem with an ASP member by contacting the member directly, ASP may be able to help.  The ASP Ombudsman can help you resolve a dispute or problem with an ASP member, but does not provide technical support for members' products.  Please write to the ASP Ombudsman at 545 Grover Road, Muskegon, MI 49442 or send a CompuServe message via CompuServe Mail to ASP Ombudsman 70007,3536


About command (Help menu)

Use this command to display the copyright notice and version number of your copy of Periodic Table.

This dialog also has a button to open the SysInfo dialog.


Enter License Info command (Help menu)

Use this command to display a dialog where you can get information on how to purchase the non-shareware version of Periodic Table.  You can also open an order form dialog to fill out an electronic order form to send to SMI Corporation.

Click Cancel if you do not want to open an order form.


How to Use the Dialogs

Use the browse buttons to view each dialog help topic or select one of the below dialogs.

About Box

System Information

Bond Characteristics

Element Properties

Element Properties Graph

Graph Data Set

Graph Properties

Atomic % to Weight %

Molecular Weight

Radioactivity Dose

Quiz Dialogs

Define User Fields

Decay Energy

Open Data Window

Open Decay Window

Font/Color (Table Window)

Font (Decay Window)

Color (Decay Window)


Periodic Table Commands

The topics that follow explain each command used by Periodic Table.  Use the above browse buttons (>> and <<)  to navigate through the commands.


Using the Table Window

See Also

The Table Window displays the Periodic Table of the Elements.  This chart is colored according to the Mode you have selected in the View/Mode Menu.  Each element box contains three items.  At the top is the atomic number of the element.  Next is the symbol for the element.  Along the bottom of the box is displayed a line of data.  The type of data shown is determined by the option chosen on the View/Detail Menu.

You can get more detail about a particular element shown on the Periodic Table by using the following procedure:

1. Move the mouse pointer over the element you want to know about.

2. Double click the left mouse button.

or

1. Use the arrow keys to highlight the element you want information on.

2. Press the Enter key.

or

1. Select the File/Open Data... command, or use the toolbar button.

A window will open giving you more information about the element.  It will show such things as who discovered the element, where it comes from and what it is used for, its atomic weight, electronegativity and much more.


Data Window

Periodic Table Commands

Periodic Law


Using the Data Window

See Also

This window is opened by double-clicking the left mouse button while the mouse pointer is positioned over an element in the Table window, by pressing Enter after highlighting an element on the Table window with the cursor keys, or by selecting the command File/Open Data.

A tabbed box is displayed.  The tabs are Statistics, Other, Info, and Isotopes.  By default the active tab is Statistics.  You can change the default by selecting the type of data you want and then select the Option Save Settings command.  You can change the data displayed by either clicking on a different tab or by selecting the data type from the View menu.

The top of the window shows the element's symbol and name.  This information is shown no matter what tab is the current tab.

Statistics

The icon on the left shows a representation of the element.  For example, the element gold (Au) has an icon showing a gold bar.  Next to the icon is a label that changes depending on the type of element displayed.  Choose that topic in the Help menu to get general information about that type of element.  The icon on the right is a representation of the element's crystal structure.  Next to the icon is the name of the type of structure.  To the right of that are the lattice parameters for the common form of the element.

The window shows the following additional information on the element: Atomic number, Atomic weight, Number of elections in each shell, the filling orbital, Melting point, Boiling point, Covalent radius, Atomic radius, Ionic radius, Atomic volume, Electronegativity (Paulings), Oxidation states, First, second and third ionization potentials, Specific heat, Heat of fusion, Heat of vaporization, Thermal conductivity, Electrical conductivity, Density, and Valence.

Other

If the Other tab is selected the window will show some additional statistical information on the element: Coefficient of thermal expansion, Modulus of elasticity, three user defined fields, X-ray emission energy, X-ray absorption energy, and X-ray fluorescent yield.

You can name the user defined fields by selecting the Option/Name User Fields... command. This will open a dialog box which will allow you to name the fields and assign a unit type to the fields.  The unit type is optional.  If it is entered then any data in that field will have the unit displayed next to the field.

Info

If the Info. tab is selected, the pronunciation of the element name, origin of the name, a description of the element, the discoverer of the element, discoverer's country, when it was discovered, where the element is usually obtained, and some of its uses, are displayed.

Isotopes

If the Isotopes tab is selected, then all isotopes (nuclides) in the database for this element are shown.  Also displayed for each nuclide are abundance, mass, spin, half-life, and decay modes.

You can change the data being shown by choosing the data type you want from the View menu.  You can also change the data shown by clicking the right mouse button and selecting an item from the menu displayed.  The information displayed may be copied to the clipboard by pressing Ctrl+C.  You can change the element displayed by using the Period and Group menus.

If the indicator READ is not displayed in the status window, you can modify the data that is displayed.  When a change is made the Save Toolbar button will be enabled, indicating that the data has been changed.  If you close the window with unsaved data, you will be prompted as to what you want to do with your changes. You can prevent any changes from being made by selecting the Option/Read Only command.

You cannot make any changes to the data displayed on the Isotope tab or the X-ray data on the Other tab in this release, regardless of the setting of the READ indicator.


Table Window

Periodic Table Commands

Periodic Law

Radioactive Decay

Isotopes


Using the Decay Tree Window

See Also

This window is opened by selecting an isotope from the Decay Menu on the Data window, or double clicking on a nuclide shown on the Isotope tab of the Data window, or by selecting a nuclide from the dialog displayed after selecting the File/Open Decay... command.

This window will display a tree showing the radioactive decay of the isotope selected.  The selected isotope is displayed near the upper left corner of the window.  Its mode of decay is given next to an arrow pointing to the daughter nuclide.  Arrows going to the right are alpha particle decays.  Arrows going down are negative beta decays.  Arrows going up are positive beta (positron) decays or electron capture decays. The percentage of abundance is given next to the mode of decay.  If the nuclide has isomeric transitions between multiple metastable states, these are shown in the top and bottom margins of the nuclide box.  These will appear as shown in the examples below:

100% => gs        or      100% => m1

If a metastable state isomeric transitions to the ground state of a nuclide then gs will be displayed next to the arrow. If a metastable state has a mode of decay other than isomeric transition, its modes are shown next to the appropriate arrows with a suffix of m , m1, or m2 to indicate which metastable state it belongs to.

The symbols used in the decay tree are:

α	alpha decay

β−	beta decay

β−β−	double beta decay

β+	positron decay

EC	electron capture

IT	isomeric transition

SF	spontaneous fission

The Decay Tree window will beep when it has completed generating the decay tree.  Some trees will take several seconds to build.

Use the scroll bars or the arrow keys to view all parts of the tree if it is too large to fit in the window.

You can double click on a nuclide box to get energy of decay information.


Data Window

Periodic Table Commands

Periodic Law

Radioactive Decay


Using the Legend

A legend can be displayed with Table and Decay windows.  The legend will be displayed whenever the Legend option is turned on.  The default is to display a legend.

To change a color click on the color box to the left of the group name.  The Color dialog box will open.  You can then change the color.

To remove the Legend you can uncheck Legend from the Options Menu.

To turn the Legend back on check Legend on the Options Menu.

The information displayed in the Table Legend depends on the Mode selected from the View/Mode menu.

Group Mode:

The Legend shows the colors used to represent each group of the Periodic Table.

Date Mode:

The Legend shows the year and the colors used to represent the discovery status of the elements on that date.  The date is changed by using the horizontal scroll bar or you may directly enter the date into the edit box on the legend.

Temperature Mode:

The Legend shows the temperature in Kelvin, Celsius, and Fahrenheit, and the colors used to represent the physical state of the elements at that temperature.  The temperature is changed by using the horizontal scroll bar or you may directly enter the Kelvin temperature into the edit box on the legend.

Metal Status Mode:

The Legend shows the three general types of elements; Metal, Non-metal and Metalloid along with the color used to represent it.

Decay Tree Legend

The legend shows the colors used to represent the half-lives of the various nuclides.


File menu commands

The File menu offers the following commands:

Open Data	Opens a new Data window.
Open Decay	Opens a new Decay window.
Close	Closes an opened window.
Reset Database	Resets the database back to its default values.
Save	Saves an opened window.  Available only in a Data window.
Print	Prints a window.
Print Preview	Displays the report on the screen as it would appear printed.
Print Setup	Selects a printer and printer connection.
Exit	Exits Periodic Table.


Edit menu commands

The Edit menu on the Table and Decay windows offers the following commands:

Copy	Copies the window to the clipboard.

The Edit menu on the Data window offers the following commands

Copy All	Copy all data to the clipboard.
Copy Statistics	Copy the statistical data to the clipboard.
Copy Info	Copy the informational data to the clipboard.
Copy Isotope	Copy the isotope data to the clipboard.


View menu commands

The View menu offers the following commands in all documents:

Toolbar	Shows or hides the toolbar.
Status Bar	Shows or hides the status bar.

The View menu in the Table document has these additional commands.

Mode	Shows a menu to choose the type of information to be displayed in the Legend window and the way the elements are colored.
Detail	Shows a menu to choose the type of information to be displayed at the bottom of each element in the table.
Data	Open a Data window for the currently selected element.

The View menu in the Data document has these commands.

Statistics	Display the portion of information about the element referred to as 'statistical'.
Other	Display the portion of information about the current element referred to as 'other'.
Information	Display the portion of information about the current element referred to as 'Information'.
Isotope	Display the portion of information about the current element referred to as 'isotopes'.
Save Data Mode	Save the currently displayed mode to the PTOE.INI file.
Table	Open the table window if it had previously been closed.
Decay	Shows a menu to choose a nuclide (isotope) to decay.


Period menu commands (Table and Data only)

The Period menu offers the following commands, which enable you to change the currently selected element:

Next	Moves to the next period below the current element.
Previous	Moves to the previous period above the current element.


Group menu commands (Table and Data only)

The Group menu offers the following commands, which enable you to change the currently selected element:

Right	Moves to the element in the group to the right of the current element.
Left	Moves to the element in the group to the left of the current element.


Tools menu commands

The Tools menu offers the following commands, which enable you to do a variety of tasks:

Bond Character	Opens a dialog to view bonds between two elements.
Element Properties	Opens a dialog to view the properties of the elements.
Atomic % to Weight %	Opens a dialog to calculate the weight percent of a mixture.
Molecular weight calculator	Opens a dialog to calculate the molecular weight of a compound.
Radiation Dose Estimator	Opens a dialog to estimate the radiation dose received from a source.
Quiz	Opens a menu to select a quiz.


Options menu commands

The Options menu offers the following commands, which enable you to change the default behavior of Periodic Table:

Table window:

Font/Color	Opens a dialog to change the font and colors used in the table.
Legend	Turns the legend on and off.
Table Full Window	Maximizes the table window on start up.
Print Colors	Prints reports in color or dithered on monochrome printers.
Group Title	Select the type of group title you prefer for the table.
Save Settings	Save current settings for subsequent start ups.
Data window:

Read Only	Disallows changes to the data in the window.
Name User Fields	Opens a dialog to name and assign units to the user defined fields.
Decay window:

Font	Opens a dialog to change the font used in the decay tree.
Colors	Opens a dialog to change the colors used in the decay tree.
Legend	Turns the legend on and off.
Print Colors	Prints reports in color or dithered on monochrome printers.
Save Settings	Save current settings for subsequent start ups.


Window menu commands

The Window menu offers the following commands, which enable you to arrange multiple views of multiple windows in the application window:

Cascade	Arranges windows in an overlapped fashion.
Tile	Arranges windows in non-overlapped tiles.
Arrange Icons	Arranges icons of closed windows.
Window 1, 2, ...	Goes to specified window.


Help menu commands

The Help menu offers the following commands, which provide you assistance with this application:

Index	Offers you an index to topics on which you can get help.
Background	Get general information about chemistry and the periodic table.
Commands	Get help information on the commands use by Periodic Table
Using Help	Provides general instructions on using help.
Order Periodic Table	Fill out an order form to purchase a copy of Periodic Table
Enter Lic. Number	Enter your license number after purchasing a copy of Periodic Table
About	Displays the version number of this application.


File Open Data command
Open Data command (File menu)

Use this command to open a Data window.  You can have multiple data windows open at once.  Use the Window menu to switch among the multiple open windows.  See Window 1, 2, ... command.

Shortcuts

Toolbar:

Keys:	CTRL+O


File Open Decay command
Open Decay command (File menu)

Use this command to open a Decay window.  You can have multiple decay windows open at once.  Use the Window menu to switch among the multiple open windows.  See Window 1, 2, ... command.

Shortcuts

Toolbar:

Keys:	CTRL+O


File Close command
Close command (File menu)

Use this command to close the active window.  Periodic Table suggests that you save changes to your Data window before you close it.  If you close a Data window without saving, you lose all changes made since the last time you saved it.

You can also close a window by using the windows Close icon, as shown below:


File Reset command
Reset Database command (File menu)

Use this command to reset the database back to its default values.  Periodic Table will ask you to confirm that you are sure you want to do this, since you will lose all change that you have made to the data.


File Save command
Save command (File menu, Data windows only)

Use this command to save the active Data window to the database.

Shortcuts

Toolbar:

Keys:	CTRL+S


File Exit command
Exit command (File menu)

Use this command to end your Periodic Table session.  You can also use the Close command on the application Control menu.  Periodic Table prompts you to save Data windows with unsaved changes.

Shortcuts

Mouse:	Double-click the application's Control menu button.

Keys:	ALT+F4


Edit Copy command
Copy command (Edit menu)

Use this command to copy the active window onto the clipboard.

Copying data to the clipboard replaces the contents previously stored there.

Shortcuts

Toolbar:

Keys:	CTRL+C


Edit Copy All command
Copy All command (Edit menu, Data window only)

Use this command to copy all the data for the active window onto the clipboard.

Copying data to the clipboard replaces the contents previously stored there.

Shortcuts

Toolbar:

Keys:	CTRL+C


Edit Copy Satistical command
Copy Stat command (Edit menu, Data window only)

Use this command to copy the statistical and other data onto the clipboard.

Copying data to the clipboard replaces the contents previously stored there.

Shortcuts

Keys:	CTRL+C


Edit Copy Info command
Copy Info command (Edit menu, Data window only)

Use this command to copy the informational data onto the clipboard.

Copying data to the clipboard replaces the contents previously stored there.

Shortcuts

Keys:	CTRL+C


Edit Copy Isotope command
Copy Iso command (Edit menu, Data window only)

Use this command to copy the isotope data onto the clipboard.

Copying data to the clipboard replaces the contents previously stored there.

Shortcuts

Keys:	CTRL+C


View Mode menu
Mode menu (View menu, Table only)

The View Mode menu offers the following commands, which change the way the table is colored:

Groups	Colors by group.
Date	Colors based on elements discovery on a certain date.
Temperature	Colors by state at a certain temperature
Metal Status	Colors by metal, non-metal, and metalloid
Shade by Value	Colors by relative position in a range of values based on the current detail.  Not available with some selected detail values. No legend is displayed.


View Mode Groups command
Groups command (View/Mode menu, Table only)

Use this command to display the table with colors indicating the which groups the elements belong to.


View Mode Dates command
Dates command (View/Mode menu, Table only)

Use this command to display the table with colors whether the element had been discovered or isolated by the year specified on the legend.


View Mode Temperature command
Temperature command (View/Mode menu, Table only)

Use this command to display the table with colors indicating the state of the element at the temperature shown on the legend.  The states can be solid, liquid, gas, or unknown.


View Mode MetalStatus command
Metal Status command (View/Mode menu, Table only)

Use this command to display the table with colors indicating whether the element is a metal, non-metal or metalloid.


View Mode Shade by Value command
Shade by Value command (View/Mode menu, Table only)

Use this command to display the table with shades of gray indicating the range of values from lowest to highest of the selected detail.

For example, if atomic radius is the current detail, then the elements would range in color from white (lowest value in range) to black (highest value in range) based on each elements atomic radius.  Any elements for which there is no value will be shown with a yellow cross-hatch.

Note: No legend is displayed.  This command may not be available depending on which Detail value has been selected.


View Detail menu
Detail menu (View menu, Table only)

The View Detail menu offers the following commands, which change the data displayed on the last line of each element box:

Atomic weight	Display atomic weight.
Electrons	Display electrons in each shell.
Filling Shell	Display the filling orbital
Electronegativity	Display electronegativity
Atomic radius	Display atomic radius
Covalent radius	Display covalent radius
Atomic volume	Displays atomic volume
Specific Heat	Display specific heat
Density	Display density
1st ionization pot	Display 1st ionization potential
2nd ionization pot	Display 2nd ionization potential
3rd ionization pot	Display 3rd ionization potential
Heat of vaporization	Display heat of vaporization
Heat of fusion	Display heat of fusion
Discovery date	Display date of discovery or isolation
Electrical conductivity	Display electrical conductivity
Thermal conductivity	Display thermal conductivity
Ionic radius	Display ionic radius
Melting point	Display melting point
Boiling point	Display boiling point


View Detail Atomic weight command
Atomic weight command (View/Detail menu, Table only)

Use this command to display the atomic weight of each element on the bottom of each element box.


View Detail Electrons command
Electrons command (View/Detail menu, Table only)

Use this command to display the electron configuration of each element on the bottom of each element box.


View Detail Filling shell command
Filling shell command (View/Detail menu, Table only)

Use this command to display the filling subshell of each element on the bottom of each element box.


View Detail Electronegativty command
Electronegativity command (View/Detail menu, Table only)

Use this command to display the electronegativity (Paulings) of each element on the bottom of each element box.


View Detail Atomic radius command
Atomic radius command (View/Detail menu, Table only)

Use this command to display the atomic radius of each element on the bottom of each element box.


View Detail Covalent radius command
Covalent radius command (View/Detail menu, Table only)

Use this command to display the covalent radius of each element on the bottom of each element box.


View Detail Atomic volume command
Atomic volume command (View/Detail menu, Table only)

Use this command to display the atomic volume of each element on the bottom of each element box.


View Detail Specific heat command
Specific heat command (View/Detail menu, Table only)

Use this command to display the specific heat of each element on the bottom of each element box.


View Detail Density command
Density command (View/Detail menu, Table only)

Use this command to display the density of each element on the bottom of each element box.


View Detail 1st ionization potential command
1st ionization potential command (View/Detail menu, Table only)

Use this command to display the 1st ionization potential of each element on the bottom of each element box.


View Detail 2nd ionization potential command
2nd ionization potential command (View/Detail menu, Table only)

Use this command to display the 2nd ionization potential of each element on the bottom of each element box.


View Detail 3rd ionization potential command
3rd ionization potential command (View/Detail menu, Table only)

Use this command to display the 3rd ionization potential of each element on the bottom of each element box.


View Detail Heat of vaporization command
Heat of fusion command (View/Detail menu, Table only)

Use this command to display the heat of fusion of each element on the bottom of each element box.


View Detail Heat of fusion command
Heat of vaporization command (View/Detail menu, Table only)

Use this command to display the heat of vaporization of each element on the bottom of each element box.


View Detail Discovery date command
Discovery date command (View/Detail menu, Table only)

Use this command to display the date of discovery or isolation of each element on the bottom of each element box.


View Detail Electrical conductivity command
Electrical conductivity command (View/Detail menu, Table only)

Use this command to display the electrical conductivity of each element on the bottom of each element box.


View Detail Thermal conductivity command
Thermal conductivity command (View/Detail menu, Table only)

Use this command to display the thermal conductivity of each element on the bottom of each element box.


View Detail Ionic radius command
Ionic radius command (View/Detail menu, Table only)

Use this command to display the ionic radius of each element on the bottom of each element box.


View Detail Melting point command
Melting point command (View/Detail menu, Table only)

Use this command to display the melting point of each element on the bottom of each element box.


View Detail Boiling point command
Boiling point command (View/Detail menu, Table only)

Use this command to display the boiling point of each element on the bottom of each element box.


View Data command
Data command (View menu, Table only)

Use this command to open a Data window for the currently selected element.


View Statistical command
Statistics command (View menu, Data only)

Use this command to display the portion of information about the current element referred to as 'statistical'.  This information consists of the atomic number, atomic weight, electronegativity, density, atomic radius, covalent radius, atomic volume, specific heat, density, first ionization potential, heat of vaporization, heat of fusion, and discovery date.

Shortcut

Click on the tab in the Data window.


View Other command
Other command (View menu, Data only)

Use this command to display the portion of information about the current element referred to as 'other'.  This information consists of the three user defined fields and the X-ray information.

Shortcut

Click on the tab in the Data window.


View Information command
Information command (View menu, Data only)

Use this command to display the portion of information about the current element referred to as 'Information'.  This data consists of who discovered the element, where it was discovered, what its uses are, etc.

Shortcut

Click on the tab in the Data window.


View Isotope command
Isotope command (View menu, Data only)

Use this command to display the portion of information about the current element referred to as isotopes.  This data consists of all the isotopes in the database for this element along with their spin, half-life, decay mode, abundance, and mass.

Shortcut

Click on the tab in the Data window.


View Save Data Mode command
Save Data Mode command (View menu, Data only)

Use this command to save the currently displayed mode to the PTOE.INI file.  Then each time a new Data window is opened the type of data set by the mode will be the one initially shown.


View Table command
Table command (View menu, Data only)

Use this command to open the table window if it had previously been closed.  If a table window is open then the command is not available.


View Decay menu
Decay menu (View menu, Data only)

This menu will only be available on the menu if there are isotopes of the element that are unstable.  Choosing a command from this menu will open a Decay Tree Window for the isotope selected.


View Toolbar command
Toolbar command (View menu)

See Toolbar for help on using the toolbar.

Use this command to display and hide the Toolbar, which includes buttons for some of the most common commands in Periodic Table, such as File Open Data.  A check mark appears next to the menu item when the Toolbar is displayed.


Toolbar

The toolbar is displayed across the top of the application window, below the menu bar.  The toolbar provides quick mouse access to many tools used in Periodic Table,

To hide or display the Toolbar, choose Toolbar from the View menu or press Ctrl+T.

Click	To

Open a new Data window.

Open a new Decay window.

Save the Data in the database.  Available only on the Data window and only if the data has been changed.

Copy the window data to the clipboard.

Print the active report.

Print Preview the active report.

Skip to the element in the next period.  (Table & Data only)

Skip to the element in the previous period.  (Table & Data only)

Skip to the element in the group to the right.  (Table & Data only)

Skip to the element in the group to the left.  (Table & Data only)

Start the Bond Characteristics dialog box.

Start the Element Properties dialog box.

Start the Atomic Weight % to Weight % dialog box.

Start the Molecular Weight dialog box.

Start the Radioactivity Dose Estimator dialog box.

Start the About dialog box.

Enter context sensitive Help mode to obtain help on some portions of Periodic Table


View Status Bar Command
Status Bar command (View menu)

See Status Bar for help on using the status bar.

Use this command to display and hide the Status Bar, which describes the action to be executed by the selected menu item or depressed toolbar button, and keyboard latch state. A check mark appears next to the menu item when the Status Bar is displayed.


Status Bar

The status bar is displayed at the bottom of the Periodic Table window.  To display or hide the status bar, use the Status Bar command in the View menu.

The left area of the status bar describes actions of menu items as you use the arrow keys to navigate through menus.  This area similarly shows messages that describe the actions of toolbar buttons as you depress them, before releasing them.  If after viewing the description of the toolbar button command you wish not to execute the command, then release the mouse button while the pointer is off the toolbar button.

The right areas of the status bar indicate which of the following keys are latched down:

Indicator	Description

12:00 PM	The current time.

READ	The current document cannot be changed.

CAP	The Caps Lock key is latched down.

NUM	The Num Lock key is latched down.

SCRL	The Scroll Lock key is latched down.


Period Next command
Next command (Period menu, Table and Data only)

This command will change the current element on the Table to be the one in the next period.  You can use the arrow keys to perform this task.

When this command is used on the Data window, it will display the data on the element in the next period without opening a new Data window.

Shortcuts

Toolbar:

Keys:	CTRL+⇓


Period Previous command
Previous command (Period menu, Table and Data only)

This command will change the current element on the Table to move to the one in the previous period.  You can use the arrow keys to perform this task.

When this command is used on the Data window, it will display the data on the element in the previous period without opening a new Data window.

Shortcuts

Toolbar:

Keys:	CTRL+⇑


Group Right command
Right command (Group menu, Table and Data only)

This command will change the current element on the Table to move to the one in the group to the right.  You can use the arrow keys to perform this task.

When this command is used on the Data window, it will display the data on the element in the group to the right without opening a new Data window.

Shortcuts

Toolbar:

Keys:	CTRL+⇒


Group Left command
Left command (Group menu, Table and Data only)

This command will change the current element on the Table to move to the one in the group to the left.  You can use the arrow keys to perform this task.

When this command is used on the Data window, it will display the data on the element in the group to the left without opening a new Data window.

Shortcuts

Toolbar:

Keys:	CTRL+⇐


Tools Bond Character command
Bond Character command (Tools menu)

This command will display a bond character dialog box that will allow you to compare chemical bond characteristics of two elements.

Choose any element in the dropdown listbox for the first and second element.  When you choose an element, its electronegativity is displayed below its name.  The difference between the two is shown along with the ionic character of the bond.  Also shown is the type of bond: covalent non-polar, covalent polar and ionic.  The percent ionic and percent covalent character of the bond are also shown.

When you have finished press the Done button.  The Help button will bring up a help topic about the dialog box.

Shortcuts

Toolbar:

Keys:	CTRL+B


Tools Element Properties command
Element Properties command (Tools menu)

This command will display a properties dialog box that will list the elements by various properties, in ascending or descending order.  You may print or graph the list.

Property/Element:

This list box shows the element property followed by the element name.  The element names are prefixed by their atomic number.  The property being listed is the one named in the Property combo box.  The list box is sorted in either ascending or descending order depending on which option is checked in the Sort Order box.  Elements which have no value or which have no known value for the selected property are listed last.

Property:

This combo box lists all the properties that can be listed.  When you choose a different property the Property/Element list box is immediately updated.

Sort Order:

This box has two radio buttons.  One for ascending order and one for descending order.  You may choose only one.  When you change the selection the Property/Element list box is immediately updated.

Buttons:

You may print the list in its displayed order by clicking the PRINT button.

When you wish to quit click the DONE button.  Clicking the HELP button displays a help topic about the dialog.

You can obtain a graph of the property selected by clicking the GRAPH button

Initially the graph will display only the single property you had selected when you clicked GRAPH.  You can add up to 9 other data sets by selecting the Option/Data Sets command.

You an also change the way the graph is displayed by selecting the Option/Graph Properties command.

You can print the graph by selecting the Print command.  Edit/Copy will put a copy of the graph on the clipboard.  Exit will close the graph and return you to the Element Properties dialog.

Shortcuts

Toolbar:

Keys:	CTRL+L


Tools Atomic % to Weight % command
Atomic % to Weight % command (Tools menu)

This dialog is a calculator.  It allows you to convert the composition of a compound between atomic percent and weight percent.

In some cases is it important to know the percentage of atoms of each element which are present in an alloy or compound; this is known as atomic percent. In other cases it is important to know what percentage of the overall weight of the alloy is comprised of a given element; in this case the compostion is given in weight percent.

For example, suppose you wanted to create 10 pounds of an alloy which was composed of 55% aluminum atoms and 45% nickel atoms. In this case you need to know how many pounds of aluminum and nickel to melt together in order to acheive this composition. In other words you need to convert 55% Al and 45% Ni in atomic percent to the equivalent in weight percentage.

First select whether you are converting to wieght percent or atomic percent (in the above example you would click on Weight to convert to weight percent). You then select elements from the Element list box and enter its percentage. Next click the Add to List button or press Enter. This will add the element and its percentage to one of the list boxes below it. The list box it is added to depends on whether you are converting from Weight % or Atomic %. If Weight % is selected then the program assumes you are converting from atomic percent to weight percent and the entered percentages are added to the atomic percent list box.

When you are entering the last element you can enter BAL instead of a percentage and the remaining percentage necessary to make 100% will be assigned to that element.  If the total does not make 100% then an error will occur.  Click the Convert button to perform the conversion.  If you want to do another conversion click the Clear button.

In the above example, if you enter 55 atomic % Al and 45 atomic % Ni you will see that this corresponds to an alloy which is  35.97% Al and 64.03% Ni by weight, or in other words you need 3.597 pounds of Al and 6.403 pounds of Ni to create 10 pounds of an alloy that is composed of 55% Al atoms and 45% Ni atoms.

When you have finished click the Exit button.  The Help button will bring up a help topic about the dialog box.

Shortcuts

Toolbar:

Keys:	CTRL+H


Tools Molecular Weight Calculator command
Molecular Weight Calculator command (Tools menu)

This dialog will allow you to calculate the formula weight of any compound.  Just enter its formula in the space provided then click the Calculate button.

When you have finished click the Exit button.  The Help button will bring up a help topic about the dialog box.

Shortcuts

Toolbar:

Keys:	CTRL+M


Tools Radioactivity Dosage Estimator command
Radioactivity Dose Estimator command (Tools menu)

This dialog will allow you to estimate the received dose, shielded dose rate, and unshielded dose rate of a person at a specified distance from a radioactive source with shielding.

When you have finished click the Done button.  The Help button will bring up a help topic about the dialog box.

Shortcuts

Toolbar:

Keys:	CTRL+E


Tools Quiz menu
Quiz menu (Tools menu)

The Tools Quiz menu offers the following commands, which begin a quiz:

Element Name	Quiz where an element symbol is given and you must choose the correct name.
Element Symbol	Quiz where an element name is given and you must choose the correct symbol.
Element Group	Quiz where an element name is given and you must choose the correct Group to which it belongs.
Atomic Number	Quiz where an element name is given and you must choose the correct atomic number.


Any Quiz command
Any Quiz command (Tool/Quiz menu)

Each quiz will go through all the elements.  None will be repeated.  If an incorrect answer is entered then you are given a second chance to answer the question.  All quizzes have the same format. They all look similar to, and work the same as any of  the other quizzes.

Score:

This box is common to all the quizzes.  It displays the number of questions asked and the number of your responses that were correct.  Below this is displayed the percentage of correct responses.

Once you have selected the proper answer, click the OK button or press the Enter key.  When you wish to quit click the QUIT button.  Clicking the HELP button displays a help topic.

Element Name Quiz-

Element Name:

This box shows the name of an element from the periodic table.  This is the name that you must match with its proper symbol.

Symbol:

This group of radio buttons allows you to choose the symbol that belongs to the name shown at the left.

Element Symbol Quiz-

Element Symbol:

This box shows the symbol for an element from the periodic table.  This is the symbol that you must match with its proper name.

Name:

This group of radio buttons allows you to choose the name that corresponds to the symbol shown at the left.

Element Group Quiz-

Element Name:

This box shows the name of an element from the periodic table.  This is the name that you must match with periodic group to which it belongs.

Group:

This group of radio buttons allows you to choose the periodic group that the element named at the left belongs to.

Atomic Number Quiz-

Element Name:

This box shows the name of an element from the periodic table.  This is the name that you must match with its proper atomic number.

Atomic Number:

This group of radio buttons allows you to choose the atomic number that belongs to the name shown at the left.


Option Title menu
Group Title menu (Option menu, Table only)

The Option Group Title menu offers the following commands:

IUPAC Groups	Changes the group names to be the new IUPAC standard.
Old IUPAC Groups	Changes the group names to be the old IUPAC standard.
CAS Groups	Changes the group names to be the ones selected by the CAS.


IUPAC Groups command
IUPAC Groups Command (Option Group Title menu, Table only)

See Also

Changes the group names to be the new IUPAC standard. Which numbers the groups from 1 through 18 starting with Hydrogen and ending with Helium.

Be sure to use the Save Settings command if you want the change to be permanent.


Old IUPAC Groups command
Old IUPAC Groups Command (Option Group Title menu, Table only)

See Also

Changes the group names to be the old IUPAC standard. Which numbers the groups IA, IIA, IIIA, IVA, VA, VIA, VIIA, VIIIA, IB, IIB, IIIB, IVB, VB, VIB, VIIB and VIIIB starting with Hydrogen and ending with Helium.

Be sure to use the Save Settings command if you want the change to be permanent.


CAS Groups command
CAS Groups Command (Option Group Title menu, Table only)

See Also

Changes the group names to be the CAS standard. Which numbers the groups IA, IIA, IIIB, IVB, VB, VIB, VIIB, VIIIB, IB, IIB, IIIA, IVA, VA, VIA, VIIA and VIIIA starting with Hydrogen and ending with Helium.

Be sure to use the Save Settings command if you want the change to be permanent.


Font/Color command
Font/Color command (Option menu, Table only)

See Also

Opens a dialog box showing the current font and color.  Make any changes you desire, (the changes will be previewed in the sample window) then choose the OK button

Once the options have been selected press the OK button to see them.  You may press the CANCEL button to abort changing any of the current options.


Font/Color dialog box

Choose Font dialog box

Choose Color dialog box


Old IUPAC Groups

CAS Groups


IUPAC Groups

CAS Groups


IUPAC Groups

Old IUPAC Groups


Option Table Full Screen command
Table Full Window command (Option menu, Table Only)

This command indicates whether the Table window will start up maximized each time Periodic Table is started.  If the menu item is checked the Table window will start maximized, otherwise it will not.


Option Print Colors command
Print Colors command (Option menu, Table and Decay Only)

This command indicates whether or not you want the colors printed when you print the periodic table.  If you do not have a color printer the Windows printer driver will attempt to create a dithered pattern to simulate the color.  If you do not want dithered colors printed, uncheck this item.


Option Save Settings command
Save Settings command (Option menu, Table and Decay Only)

Selecting this command will cause Periodic Table to save its current options to the PTOE.INI file.  These options will be used the next time you start Periodic Table.


Option Read Only command
Read Only command (Option menu, Data Only)

Selecting this command will make the Data window read only.  This means that you will not be able to change any fields in the window.  Selecting the command again will turn Read Only off.  When the window is read only then you will see a READ indicator in the status bar.


Option Name User Fields command
Name User Fields command (Option menu, Data Only)

This command will display a dialog box that will allow you to define names for the user fields.

The Periodic Table database contains 3 user defined fields.  You may use these fields for any data you wish to maintain.  This dialog allows you to give the fields a meaningful name and optionally a unit.

You can also set up a unit for the field.  Setting up a unit will keep you from having to enter the units into the same field as the user defined fields.


Option Font command
Font command (Option menu, Decay Only)

This box shows the current font that is used to draw the Decay Tree window. Select the font you want to use and click OK.  Any change made here will be previewed in the sample window.


Option Colors command
Colors command (Option menu, Decay Only)

This menu displays the color categories used in the Decay Tree window.  Select the category you want to change, then a Color dialog box will be displayed.  It works the same as the Color dialog that is displayed when you use the Option/Font/Color command on the Table window.  Click the OK button when you have made your change.  Clicking Cancel will abort any change you may have made.  For a sample of the Color dialog see Colors dialog.


Cascade command (Window menu)

Use this command to arrange multiple opened windows in an overlapped fashion.


Tile command (Window menu)

Use this command to arrange multiple opened windows in a non-overlapped fashion.


Window Arrange Icons command (Window menu)

Use this command to arrange the icons for minimized windows at the bottom of the main window.  If there is an open window at the bottom of the main window, then some or all of the icons may not be visible because they will be underneath this window.


1, 2, ... command (Window menu)

Periodic Table displays a list of currently open windows at the bottom of the Window menu.  A check mark appears in front of the name of the active window.  Choose a window from this list to make it active.


Index command (Help menu)

Use this command to display the opening screen of Help.  From the opening screen, you can jump to step-by-step instructions for using Periodic Table and various types of reference information.

Once you open Help, you can click the Contents button whenever you want to return to the opening screen.


Using Help command (Help menu)

Use this command for instructions about using Help.


Order Periodic Table command (Help menu)

Use this command to display an on-line order form.  Fill out the requested information and click the OK button.  An order form will be printed that you can send to SMI along with the payment.

Click Cancel if you do not want to print the form.


Help Using Help Command
Context Help command  (Help menu)

Use the Context Help command to obtain help on some portion of Periodic Table.  When you choose the Toolbar's Context Help button, the mouse pointer will change to an arrow and question mark.  Then click somewhere in the Periodic Table window, such as another Toolbar button.  The Help topic will be shown for the item you clicked.

Shortcut

Keys:	SHIFT+F1


Title Bar

The title bar is located along the top of a window.  It contains the name of the application and document.

To move the window, drag the title bar.  Note: You can also move dialog boxes by dragging their title bars.

A title bar may contain the following elements:

Application Control-menu button

Document Control-menu button

Maximize button

Minimize button

Name of the application

Name of the document

Restore button


Scroll bars

Displayed at the right and bottom edges of the document window.  The scroll boxes inside the scroll bars indicate your vertical and horizontal location in the document.  You can use the mouse to scroll to other parts of the document.

There are no scroll bars on the Table window.  It resizes itself to match the window dimensions.


Size command (System menu)

Use this command to display a four-headed arrow so you can size the active window with the arrow keys.

After the pointer changes to the four-headed arrow:

1.	Press one of the DIRECTION keys (left, right, up, or down arrow key) to move the pointer to the border you want to move.

2.	Press a DIRECTION key to move the border.

3.	Press ENTER when the window is the size you want.

Note:  This command is unavailable if you maximize the window.

Shortcut

Mouse:	Drag the size bars at the corners or edges of the window.


Move command (Control menu)

Use this command to display a four-headed arrow so you can move the active window or dialog box with the arrow keys.

Note:  This command is unavailable if you maximize the window.

Shortcut

Keys:	CTRL+F7


System Minimize Command
Minimize command (application Control menu)

Use this command to reduce the Periodic Table window to an icon.

Shortcut

Mouse:	Click the minimize icon [image] on the title bar.

Keys:	ALT+F9


Maximize command (System menu)

Use this command to enlarge the active window to fill the available space.

Shortcut

Mouse:	Click the maximize icon [image] on the title bar; or double-click the title bar.

Keys:	CTRL+F10 enlarges a document window.


Next Window command (document Control menu)

Use this command to switch to the next open document window.  Periodic Table determines which window is next according to the order in which you opened the windows.

Shortcut

Keys:	CTRL+F6


Previous Window command (document Control menu)

Use this command to switch to the previous open document window.  Periodic Table determines which window is previous according to the order in which you opened the windows.

Shortcut

Keys:	SHIFT+CTRL+F6


Close command (Control menus)

Use this command to close the active window or dialog box.

Double-clicking a Control-menu box is the same as choosing the Close command.

Note:  If you have multiple windows open for a single document, the Close command on the document Control menu closes only one window at a time.  You can close all windows at once with the Close command on the File menu.

Shortcuts

Keys: 	CTRL+F4 closes a document window

ALT+F4 closes the Periodic Table window or dialog box


Restore command (Control menu)

Use this command to return the active window to its size and position before you chose the Maximize or Minimize command.


Switch to command (application Control menu)

Use this command to display a list of all open applications.  Use this "Task List" to switch to or close an application on the list.

Shortcut

Keys:	CTRL+ESC

Dialog Box Options

When you choose the Switch To command, you will be presented with a dialog box with the following options:

Task List

Select the application you want to switch to or close.

Switch To

Makes the selected application active.

End Task

Closes the selected application.

Cancel

Closes the Task List box.

Cascade

Arranges open applications so they overlap and you can see each title bar.  This option does not affect applications reduced to icons.

Tile

Arranges open applications into windows that do not overlap.  This option does not affect applications reduced to icons.

Arrange Icons

Arranges the icons of all minimized applications across the bottom of the screen.


Choose Font Dialog
Choose Font dialog box

Select the font you want to use.  Then click the OK button.  If you click Cancel then no changes will be made.  You cannot change the font style or size.  Periodic Table will select them for you based on the current window size.


Choose Color Dialog
Choose Color dialog box

Select the color you wish to use.  Then click OK.  If you click Cancel then no changes will be made.

Some color combinations may be easier to read than others.  Some color combinations will not print as well as others.  You will need to experiment to get the best color combination for you particular situation.


Font/Color Dialog
Font/Color dialog box

See Also

Opens a dialog box showing the current font and color.  Make any changes you desire, (the changes will be previewed in the sample window) then choose the OK button.  The CANCEL button will exit the dialog without making any changes.

Font:

This box shows the current font that is used to draw the Periodic Table.  By clicking on the change button you will see a Font dialog box open.  Select the font you want to use and click OK.  Any change made here will be previewed in the sample window:

Color for Item:

This group of controls allows you to change the colors of the element groups.

The first control is a combo box that contains all the element groups.  When you have selected the group you want to change, press the SET button.  This will bring up the Color dialog box.  This will allow you to change the color of the group.  Any change you make here will be reflected in the sample window.

Once the above options have been selected press the OK button to see them.  You may press the CANCEL button to abort changing any of the current options.


Choose Font dialog box

Choose Color dialog box


Atomic % to Weight % Dialog
Atomic % to Weight % dialog box

This dialog is a calculator.  It allows you to convert the composition of a compound between atomic percent and weight percent.

In some cases is it important to know the percentage of atoms of each element which are present in an alloy or compound; this is known as atomic percent. In other cases it is important to know what percentage of the overall weight of the alloy is comprised of a given element; in this case the compostion is given in weight percent.

For example, suppose you wanted to create 10 pounds of an alloy which was composed of 55% aluminum atoms and 45% nickel atoms. In this case you need to know how many pounds of aluminum and nickel to melt together in order to acheive this composition. In other words you need to convert 55% Al and 45% Ni in atomic percent to the equivalent in weight percentage.

First select whether you are converting to wieght percent or atomic percent (in the above example you would click on Weight to convert to weight percent). You then select elements from the Element list box and enter its percentage. Next click the Add to List button or press Enter. This will add the element and its percentage to one of the list boxes below it. Which list box it is added to depends on whether you are converting from Weight % or Atomic %. If Weight % is selected then the program assumes you are converting from atomic percent to weight percent and the entered percentages are added to the atomic percent list box.

When you are entering the last element you can enter BAL instead of a percentage and the remaining percentage necessary to make 100% will be assigned to that element.  Click the Convert button to perform the conversion.  If you want to do another conversion click the Clear button.

In the above example, if you enter 55 atomic % Al and 45 atomic % Ni you will see that this corresponds to an alloy which is  35.97% Al and 64.03% Ni by weight, or in other words you need 3.597 pounds of Al and 6.403 pounds of Ni to create 10 pounds of an alloy that is composed of 55% Al atoms and 45% Ni atoms.

When you have finished click the Exit button.  The Help button will bring up a help topic about the dialog box.


Molecular Weight Dialog
Molecular Weight dialog box

This dialog will allow you to calculate the formula weight of any compound.

Type the chemical formula in the edit field.  Then click the Calculate button or press Enter.  The following are examples of acceptable formulas: H2O HOH H(OH) Ca(OH)2 CuSO4.5H2O (NH4)2SO4.  The element symbols you enter are case sensitive.

When you have finished click the Exit button.


Radioactivity Dosage Estimator Dialog
Radioactivity Dosage Estimator dialog box

This dialog will allow you to estimate the received dose, shielded dose rate and unshielded dose rate of a person at a specified distance from a radioactive source with shielding.

First you enter either the acitivity of the source in curies or you can enter a measured dose rate at a specific distance from the source.

You then enter the distance from the source, the hours of exposure, and the shielding type and thickness.

Click the Calculate button and the answers are displayed at the bottom of the box.

When you have finished, click the Done button.  The Help button will bring up this help topic about the dialog box.


Bond Character Dialog
Bond Character dialog box

This command will display a dialog box that will allow you to compare chemical bond characteristics of two elements.

Choose any element in the dropdown listbox for the first and second element.  When you choose an element, its electronegativity is displayed below its name.  The difference between the two is shown along with the ionic character of the bond.  Also shown is the type of bond: covalent non-polar, covalent polar and ionic.  The percent ionic and percent covalent character of the bond are also shown.

When you have finished press the Done button.  The Help button will bring up a help topic about the dialog box.


Element Properties Dialog
Element Properties dialog box

This command will display a dialog box that will list the elements by various properties, in ascending or descending order.  You may print or graph the list.

Property/Element:

This list box shows the element property followed by the element name.  The element names are prefixed by their atomic number.  The property being listed is the one named in the Property pull down box.  The list box is sorted in either ascending or descending order depending on which option is checked in the Sort Order box.  Elements which have no value or which have no known value for the selected property are listed last.

Property:

This pull down box lists all the properties that can be listed.  When you choose a different property the Property/Element list box is immediately updated.

Sort Order:

This box has two radio buttons.  One for ascending order and one for descending order.  You may choose only one.  When you change the selection the Property/Element list box is immediately updated.

Buttons:

You may print the list in its displayed order by clicking the PRINT button.

When you wish to quit click the DONE button.  Clicking the HELP button displays a help topic about the dialog.

You can obtain a graph of the property selected by clicking the GRAPH button.


Property Graph Dialog
Property Graph dialog box

You can obtain a graph of the property selected on the Element Property dialog by clicking the GRAPH button.

Initially the graph will display only the single property you had selected when you clicked GRAPH.  You can add up to 9 other data sets by selecting the Option/Data Sets command.

You can change the way the graph looks by using the Option/Properties command.

Use the Edit/Copy command to place a copy of the graph on the clipboard.

Use the File/Print command to print the graph.

You can exit the graph by selecting the File/Exit command.  You will then return to the Element Properties dialog.


Graph Data Dialog
Graph Data dialog box

Initially the graph will display only the single property you had selected when you clicked GRAPH.  You can add up to 9 other data sets by using this dialog.  You can then select any 10 data sets shown.

Click Cancel if you dont want to make any changes.

You an also change the way the graph is displayed by selecting the Option/Graph Properties command.


Graph Properties Dialog
Graph Properties dialog box

This dialog is displayed when you select the Option/Graph Properties command.  Here you can change many of the graphs properties.

Most of the controls on this dialog are self-explanatory.  The controls in the Font group control the font used by the graph labels.  The controls in the Graph Title group control the title and font for the title.  The Data Set list box is disabled unless there is more than one data set being displayed on this graph.  If it is enabled then the controls to its right are the current settings for the selected data set.

The small graph displayed in the upper left corner of the dialog will change to give you a preview of any changes you make to the graph properties.  Click OK to accept your changes and return to the graph.  Cancel will ignore any changes you made and return you to the graph.


Quiz Dialog
Quiz dialog box

Each quiz will go through all the elements.  None will be repeated.  If an incorrect answer is entered then you are given a second chance to answer the question.  All quizzes have the same format.  They all look similar and work the same as any of the other quizzes.

Score:

This box is common to all the quizzes.  It displays the number of questions asked and the number of your responses that were correct.  Below this is displayed the percentage of correct responses.

Once you have selected the proper answer click the OK button or press the Enter key.  When you wish to quit click the QUIT button.  Clicking the HELP button displays a help topic.

The descriptions of the quizzes will describe the differences between them.

Element Name - Ctrl+N

This quiz will display an element name and you must choose the correct symbol.

Element Name:

This box shows the name of an element from the periodic table.  This is the name that you must match with its proper symbol.

Symbol:

This group of radio buttons allows you to choose the symbol that belongs to the name shown at the left.

Element Symbol - Ctrl+S

This quiz will display an element symbol and you must choose the correct name.

Element Symbol:

This box shows the symbol for an element from the periodic table.  This is the symbol that you must match with its proper name.

Name:

This group of radio buttons allows you to choose the name that corresponds to the symbol shown at the left.

Element Group - Ctrl+G

This quiz will display an element name and you must choose the correct periodic group to which it belongs.

Element Name:

This box shows the name of an element from the periodic table.  This is the name that you must match with periodic group to which it belongs.

Group:

This group of radio buttons allows you to choose the periodic group that the element named at the left belongs to.

Atomic Number - Ctrl+A

This quiz will display an element name and you must choose the correct atomic number.

Element Name:

This box shows the name of an element from the periodic table.  This is the name that you must match with its proper atomic number.

Atomic Number:

This group of radio buttons allows you to choose the atomic number that belongs to the name shown at the left.


Name User Fields Dialog
Name User Fields dialog box

This command will display a dialog box that will allow you to define names for the user fields.

The Periodic Table database contains 3 user defined fields.  You may use these fields for any data you wish to maintain.  This dialog allows you to give the fields a meaningful name and optionally a unit.

You can also set up a unit for the field.  Setting up a unit will keep you from having to enter the units into the same field as the user defined fields.


Decay Energy Dialog
Decay Energy dialog box

This dialog will display the energies associated with the decay modes of the nuclide you have double-clicked on.

If the nuclide has metastable states then you can use the drop-down list box at the top of the dialog to select on of the other states.


Sysinfo Dialog
SysInfo dialog box

This dialog will display several key items of information about your system, such as the amount of memory and free resources remaining.


Select Element Dialog
Select Element dialog box

This command will open a Data Window for the element that is selected from the dialog box shown.

If you check the Alphabetical Order box the element list will be resorted in alphabetical order.  Click the OK button to open a data window for the selected element.


Select Nuclide Dialog
Select Nuclide dialog box

This command will open a Decay Window for the nuclide that is selected from the dialog box shown.

If you check the Alphabetical Order box the element list will be resorted in alphabetical order.  Once an element is selected the nuclides for that element will appear in the Nuclides list.  Select a nuclide from the list.  Click the OK button to open a decay window for the selected nuclide.


Printing Dialog
Printing dialog box

This dialog shows you the progress of your print request.  It also shows you what device you are printing to.


License Expiration Dialog
Evaluation License Expiration dialog box

This dialog is displayed when your 30 day or 60 use evaluation period has expired.

The time began from the time you first ran Periodic Table.  You should now stop using Periodic Table and remove it from your system, or you should purchase a license from SMI Corporation if you would like to continue using the program.

An order form has been provided in this help file.  You can also click the ORDER button and Periodic Table will let you fill in and then print an order form.


Periodic Law

It became evident early in the science of chemistry that certain elements could be grouped together by the similarities of their physical properties.  For example, lithium, sodium and potassium have similar properties as do fluorine, chlorine, bromine and iodine.

In 1829, the German chemist Döbereiner, became the first to propose a relationship between atomic weights and the properties of elements.  He was able to show that strontium has properties about midway between calcium and barium.

The English chemist Newlands, in 1865, saw a correlation between the atomic weights and the properties of the elements.  Mendeleev in Russia and Lothar Meyer in Germany, in 1870, working independently and unaware of Newlands, outlined this relationship in detail.

This led to a statement that the properties of the elements are periodic functions of their atomic weights.  The below series illustrates the point:

Li	Be	B	C	N	O	F	Ne

6.94	9.01	10.81	12.01	14.01	16.00	18.00	20.18

Na	Mg	Al	Si	P	S	Cl	Ar

22.00	24.31	26.98	28.09	30.97	32.06	35.45	39.95

In each row the elements differ quite a bit in properties.  There is, however, an interesting graduation of properties as atomic weight increases.  Note that elements in a vertical column have similar properties.  For example, lithium is similar to sodium.

Moseley showed that atomic numbers rather than atomic weights are the determining factor of chemical properties.  If you check the Periodic Table you can see that argon (At. Wt. 39.948) precedes potassium (At. Wt. 39.098).  There are other reversals in the table as well.  This is due to the abundance of heavier isotopes of some elements.  This affects the atomic weight of the element, which is an average.

The formal statement of the Periodic Law is: The properties of the elements are periodic functions of their atomic numbers.


Electron Shells

See Also

As atomic number increases so too does the number of electrons in a neutral atom of the element.  The valence electrons are largely responsible for its chemical behavior.  If elements having the same number of valence electrons are grouped together the elements in each group or family will have similar chemical properties.

The first short period contains only two elements.  These elements fill the K shell.  It ends with helium which contains a full K shell consisting of two electrons.

The second short period contains eight elements beginning with lithium and ending with neon.  Neon has a complete L shell of eight electrons.

The third short period contains eight elements beginning with sodium.  It ends with argon, which contains eight electrons in the M shell.

The fourth period contains eighteen elements beginning with potassium.  It includes a series of elements from scandium through copper.  These elements are known as transition elements.

They are building the M shell from eight to eighteen electrons.  Before this series begins though, two electrons enter the outermost N shell.  After the series the N shell then builds up to eight electrons ending with krypton.

The fifth period is just like the fourth period, in which the O shell takes two electrons then the N shell builds to eighteen electrons before the O shell continues out to eight electrons ending with xenon.

The sixth period contains 32 elements.  It too has a transition series beginning with lanthanum and ending with gold, in which the O shell fills to eighteen electrons.

Note however that this series is split after lanthanum with a series of fourteen elements.  In these elements the N shell (third from the outside) is filling from eighteen to 32 electrons.  These are referred to as the inner transition series, lanthanum series or the rare earth elements.  It begins with cerium and ends with lutetium.

Following lutetium the transition series from hafnium to gold completes by building the O shell to eighteen electrons.  The outer P shell then continues to build to eight electrons ending with radon.

The seventh period is incomplete.  The first two elements, francium and radium fill the Q shell with two electrons.  Then the P and O shells fill in the same way as the sixth period.  This produces the actinide series.


Electron Subshells


Electron Subshells

See Also

Each of the electron shells, designated by the letters K, L, M, N, O, P, and Q or the numbers 1, 2, 3, 4, 5, 6, and 7, are subdivided further into subshells.

The first principal shell, the K shell, has one subshell designated as the 1s shell.  The second principal shell has two subshells designated as 2s and 2p.  The third shell has three subshells designated 3s, 3p, and 3d.  The fourth shell has four subshells, 4s, 4p, 4d, and 4f.

The subshells are further divided into orbitals, each of which can contain a maximum of two electrons.  Therefore an s subshell, which is made up of one orbital, can contain a maximum of two electrons.  A p subshell has three orbitals and can contain six electrons.  A d subshell has five orbitals and can contain ten electrons.  An f subshell has seven orbitals and can contain fourteen electrons.

On the average, an s electron will approach the nucleus more closely than a p of the same principal shell, a p electron more closely than a d electron, and a d electron more closely than an f electron.

The notation used in describing electron structures consists of a principal shell number in front of the subshell letter and a superscript to designate the number of electrons in that particular subshell.  For example 3d4 indicates that there are four electrons in subshell d of the M shell. (Unfortunately Help does not allow super or subscripts, so just use your imagination here.)


Shapes of Electron Orbitals


Electron Orbital Shapes

The orbitals occupied by electrons in different subshells differ from each other with regard to their size, shape, and orientation in space.  The larger the number of the principal shell, the greater the volume of the corresponding orbital will be.

For example, a 2s electron has an orbital of greater volume than a 1s electron.  However, the orbitals of the higher principal shells overlap those of lower shells.  This means that the outer electrons penetrate the regions occupied by inner electrons.

The shape of an s electron orbital is spherical while that of a p electron orbital is dumbbell shaped.

The number of possible orientations of atomic orbitals in space depends to an extent on the shape of the orbital.  An s orbital still presents the same appearance to an outside observer since its shape is that of a sphere.  Therefore an s orbital is said to be spherically symmetrical and without directional characteristics.

s orbitals

It is a bit more complex with p orbitals which occur in sets of three.  It is not possible to determine the direction of any one orbital in a given set.  However, the axes along which the three p orbitals lie are mutually at right angles to each other.  The three p orbitals are designated as px, py and pz to emphasize their directional nature.

px	py	pz

The five d orbitals consist of lobe-shaped regions arranged in space as shown below.  The drawings are oriented so that the lobes of the orbitals designated dz2 and dx2-y2 lie along the axes and the lobes of the dxz, dyz, and dxy lie in between the axes.

dz2	dx2-y2

dxz	dyz	dxy

The seven f orbital are not understood well enough to have good agreement on their shape and orientation in space.  Below is shown one way of representing the f orbitals.

fx3-3/5xr2	fy3-3/5yr2	fz3-3/5zr2

fxyz	fx(z2-y2)	fy(x2-z2)

fz(x2-y2)


Crystal Structure
Crystal Structures

The elements have been classified by their crystalline structure when solidified.  Below are diagrams depicting the six basic crystal configurations.


Rare Earth Elements

See Also

These elements got their name from the fact that chemists first isolated them in their oxide forms.  These oxides somewhat resemble calcium, magnesium and aluminum oxides, sometimes called common earths.

The rare earths all have three valence electrons.  Because of this they all have similar properties.

They are found in the Lanthanide and Actinide series of elements in periods 6 and 7.


Metals

Transition Metals

Alkali Metals

Alkali Earth Metals


Transition Metal Elements

See Also

This group of metals is distinguished from other metals not by their physical properties, but by their electronic structure.  The transition metals have their valence electrons in more than one shell.  Regular, or representative, metals have their valence electrons in only one shell.

The transition metals include the elements of the groups IIIA through IIB in each of the long periods of the periodic table.

The transition metals are noted for their variability in oxidation state.  This is attributed to the presence of valence electrons in more than one shell.  Whereas, the representative metals have only one or two oxidation states, since they have valence electrons in only one shell.

Thus, manganese has two electrons in its outside shell and five electrons in the next shell down, and exhibits oxidation states of +1, +2, +3, +4, +5, +6, and +7.

They are also characterized by the fact that well into the series, going from left to right, the properties of succeeding metals do not differ greatly from preceding ones.  This is attributed to the fact that, generally, succeeding elements differ in electronic structure by one electron in the next to the outer valence shell rather than the outer shell.

In contrast, those of succeeding representative metals in a period differ extensively, since they differ by one electron in the outer valence shell.


Metals

Alkali Metals

Alkali Earth Metals

Rare Earth Metals


Alkali Metal Elements

See Also

Alkali metal is a term that refers to six elements: lithium, sodium, potassium, rubidium, cesium, and francium.  These elements make up group IA of the periodic table of elements.  They all form singly-charged positive ions, and are extremely reactive.  They react violently with water, forming hydroxides and releasing hydrogen gas and heat.  Cesium and francium are the most reactive and lithium is the least.

While not a metal in the normal sense, hydrogen generally behaves as a Group IA metal by giving up its single valence s electron.


Metals

Alkali Earth Metals

Transition Metals

Rare Earth Metals


Alkali Earth Metal Elements

See Also

Alkali earth metal is a term that refers to six elements: beryllium, magnesium, calcium, strontium, barium, and radium.  These elements make up group IIA of the periodic table of elements.  They all exhibit a single oxidation state, +2.  They are all very reactive.  Barium and radium are the most reactive and beryllium is the least.

The term "earth" was formerly used by chemists to denote slightly soluble metal oxides.  The oxides of barium, strontium, and calcium resemble alumina (Al2O3), a typical "earth", but form alkaline mixtures with water.  For this reason barium, strontium, and calcium were called alkaline earth metals.  This name has now been extended to include all of the elements of group IIA.


Metals

Alkali Metals

Transition Metals

Rare Earth Metals


Metal Elements

See Also

Chemists use a test called an electrolysis test to determine if an element is metallic or non-metallic.  This test consists of dissolving the element in acid and running an electric current through the solution.  If the element is metallic, the atoms of the element will show a positive charge.  That is they will seek the negative pole.

Formally it is stated as "those elements which, when in solution in a pure state, carry a positive charge and seek the negative pole in an electric cell".

Properties of metals that are familiar to everyone include:

1. They are good conductors of heat and electricity

2. They are usually opaque to light

3. They have metallic luster

The difference in chemical properties between metals and non-metals lies mainly in the fact that atoms of non-metals will readily fill their valence shells by sharing electrons with or transferring electrons to other atoms.

For example, chlorine, a typical non-metal, will readily enter into combination with another atom by adding one electron to an outer shell of seven: gaining an electron from or sharing a pair with the other atom.  Whereas, an atom of say sodium, a typical metal, enters into combination by the loss of its single valence electron.

Metallic characteristics of the elements decrease and non-metallic characteristics increase with the increase of valence electrons.  Also metallic characteristics increase with the number of electron shells.  Therefore there is no sharp dividing line between the metals and the non-metals.

There are elements that are definitely on the border between metal and non-metal.  These elements will show hybrid behavior.  They are sometimes called metalloids.  Many of them have been called semiconductors.  This group of elements includes boron, silicon, germanium, arsenic, antimony, tellurium, and astatine.

Their physical properties generally include:

1. They are good conductors of heat and electricity.

2. They are malleable and ductile in their solid state.

3. They show metallic luster.

4. They are opaque.

5. They have high density.

6. They are solids (except mercury)

7. They have crystal structure in which each atom is surrounded by eight or twelve near neighbors

Their chemical properties generally are:

1. They have one to four valence electrons.

2. They have low ionization potentials; they readily lose electrons.

3. They are good reducing agents.

4. They have hydroxides which are bases or amphoteric.

5. They are electropositive.

Of the 110 elements now known, only 17 show primarily non-metallic characteristics, 7 others are metalloids, and 86 may be classed as metals.


Non-Metals

Transition Metals

Alkali Metals

Alkali Earth Metals

Rare Earth Metals

Halogen Elements

Noble Gas


Halogen Elements

See Also

The halogens are the elements astatine, fluorine, chlorine, bromine, and iodine.  They are non-metals, and make up part of the seventh group in the periodic table.

The halogens all have a strong unpleasant odor and will burn flesh.  They do not dissolve well in water.

The five elements are strongly electronegative.  They are oxidizing agents, with fluorine being the strongest and astatine being the weakest.  They react with most metals and many non-metals.

As the atomic structure of  the halogens becomes more complex with increasing atomic weight there is a gradation in physical properties.  For example:  Fluorine is a pale green gas of low density.  Chlorine is a greenish-yellow gas 1.892 times as dense as fluorine.  Bromine is a deep reddish-brown liquid which is three times as dense as water.  Iodine is a grayish-black crystalline solid with a metallic appearance.  And astatine is a solid with properties which indicate that it is somewhat metallic in character.


Non-Metal Elements

Noble Gas Elements


Noble Gas Elements

See Also

Noble gas refers to any element of the group of six elements in group 8 of the periodic table.  They are argon, helium, krypton, neon, radon, and xenon.  Unlike most elements, the noble gases are monoatomic.  The atoms have stable configurations of electrons.  Therefore under normal conditions they do not form compounds with other elements.

They were generally called inert gases until about 1962 when xenon tetrafluoride, XeF4, was produced in the laboratory.  This was the first report of a stable compound of a noble gas with another single element.


Non-Metal Elements

Halogen Elements


Non-Metal Elements

See Also

Non-metals are basically defined as elements that are not metals.

Their physical properties generally include:

1. They are poor conductors of electricity and heat.

2. They are brittle, not ductile in their solid state.

3. They show no metallic luster.

4. They may be transparent or translucent.

5. They generally have a low density.

6. They are gases, liquids, or solids.

7. They form molecules which consists of atoms covalently bonded.

Their chemical properties are generally:

1. They usually have four to eight valence electrons.

2. They have high electron affinities.

3. They are good oxidizing agents.

4. They have hydroxides which are acidic.

5. They are electronegative.


Metals

Transition Metals

Alkali Metals

Alkali Earth Metals

Rare Earth Metals

Halogen Elements

Noble Gas


Radioactive Decay

To understand how nuclei break apart we must first examine how nuclei are put together.  To begin with let's study carbon-12.  Its mass is defined to be 12.0000 and all other nuclei are measured against this standard.

Carbon-12 has twelve particles in its nucleus: 6 protons and 6 neutrons.  It would then seem that each proton and neutron should have a mass of 1.0000.  However, measurements of the mass of the proton curving in a magnetic field of known strength show the mass of the proton as 1.00734.

A neutron, since it is uncharged, does not curve in a magnetic field.  But, its mass has been measured in other ways.  Chadwick, in 1934, measured the energy it took to break apart a hydrogen-2 nucleus.  The mass of the hydrogen-2 nucleus was known.  He then subtracted the mass of the proton and added the energy needed to break the nucleus up (remember that mass and energy are related by Einstein's famous equation, E=mc^2).  The mass left over was the mass of the neutron, which is 1.00867, or about .0014% heavier than the proton.

Adding up 6 protons and 6 neutrons leaves us 0.096 heavier than the mass of carbon-12.  In 1927, Aston, found that all nuclei had masses slightly less that the total mass of the protons and neutrons.  Aston called this the mass defect.

The fraction of the total mass that this mass defect consists of is called the packing fraction.  It is calculated for carbon-12 as follows.  The defect of 0.096 is divided by 12 which gives 0.008.  Scientists then multiply this number by 10,000 to avoid working with small numbers, which makes the packing fraction 80 for carbon-12.

In general, the packing fractions of all nuclei increase up to iron-56 which has a packing fraction of 94.0.  At that point the packing fractions begin to decrease until by the time you get to uranium-238 you have a packing fraction of only 79.4.  We will see a significance to iron-56 later in our discussion.

Where did the mass making up the mass defect go?  It turned into energy, of course.  When 6 protons and 6 neutrons are formed into a carbon-12 nucleus a small fraction of their mass is turned into energy and is dissipated into space.  A process that dissipates energy has a tendency to occur.  This means that protons and neutrons have a tendency to form nuclei.

To break up an atomic nucleus into its individual protons and neutrons requires energy to be supplied that is exactly equal to the amount of energy dissipated when the nucleus formed.  Except under extreme conditions this will not happen.  Once a nucleus has formed it will retain the same identity.  (Perhaps you are wondering why the nucleus holds together so well when there are so many positive charges packed so tightly together?  It would seem that the nucleus should fly apart since like charges repel each other.  To see why this does not happen see Interactions.)

But in order for a nucleus to change its identity it only has to gain or loose a proton or neutron to change into a different nucleus.  In general, if such an event takes place and results in a higher packing fraction there will be a further dissipation of energy and therefore a certain tendency for the change to take place.  From this you would expect that nuclei with lower mass numbers would change into nuclei with higher mass numbers and nuclei with high mass number to do the opposite with both processes converging on iron-56.  With its maximum packing fraction, it would require an energy input to become larger or smaller.  (This is one reason that massive stars explode into a supernova when they try to fuse iron in their cores.  It requires an energy input which cools the star and begins its collapse.)

Due to certain factors light nuclei are prevented from sliding toward iron-56 on their own.  But for massive nuclei, (nuclei more massive than bismuth-209) the tendency is realized.  They do tend to emit particles forming nuclei with higher packing fractions and dissipating energy.

The greater the dissipation of energy from one nucleus to another the more likely the change, the faster that the change will take place, and the shorter the half-life of the original nucleus.  For example, for thorium-232, uranium-235, and uranium-238 the change dissipates so little energy that their half-lives are very long.

Natural radioactivity involving nuclei with mass numbers from 232 to 238 changes them into nuclei with mass numbers from 206 to 208.  The process increases their packing fractions, dissipating energy.

Helium-4 is a very stable nucleus.  So stable that is has virtually no tendency to add either a proton or a neutron.  Among nuclei of higher mass numbers, the nuclei that can be thought of as units of helium-4 are particularly stable.  Carbon-12 (6 protons, 6 neutrons, 3 helium-4 units) and oxygen-16 (8 protons, 8 neutrons, 4 helium units) hold together tightly.  They both have lower packing fractions than their neighboring nuclei.

As nuclei get more massive this effect seems to diminish.  However, neon-20 (5 helium-4 units) magnesium-24(6), silicon-28(7), sulfur-32(8), and calcium-40(10) are particularly stable, and they are all the most common isotopes of their elements.

Beyond calcium-40 the effect loses its stabilizing effect.  It seems that as more protons are added it requires more than an equal number of neutrons to keep the nucleus stable.  So that by the time you reach iron-56 you have a nucleus of 26 protons and 30 neutrons.  Tin-118 has 50 protons and 68 neutrons.  Gold-197 has 79 protons and 118 neutrons.  Finally to bismuth-209, the heaviest stable nucleus, has 83 protons and 126 neutrons for a neutron/proton ratio of 1.52.

Past bismuth-209 no excess of neutrons will stabilize a nucleus.  When a massive nucleus is so massive it is unstable, it has a tendency to lose particles in order to become less massive and therefore more stable.  A good way to do this is to emit a helium-4 nucleus.  These helium-4 nuclei are called alpha particles, and the process is called alpha decay.

Nuclei less massive than bismuth-209 usually do not emit alpha particles.  Neodymium-144 is the lightest nucleus that does, but only very slowly.  Lighter nuclei usually emit beta particles.  A beta particle is emitted when a neutron is converted to a proton.  The charge must be conserved, so since a neutron has no charge but a proton is positively charged there must be a negative charge to balance the reaction.  The negative charge comes from the beta particle which is actually an electron.  Therefore, beta emission involves a neutron changing to a proton and an electron.  (It is actually more complicated than that, for a more detailed description see Beta Decay).


Alpha Decay

Past bismuth-209 no excess of neutrons will stabilize a nucleus.  When a nucleus is so massive it is unstable, it has a tendency to lose particles in order to become less massive and therefore more stable.  A good way to do this is to emit a helium-4 nucleus.  It is light and holds together tightly, therefore it is easy to expel as a unit.  This helium-4 unit is called an alpha particle.  Therefore, uranium-238, thorium-232, radium-226 and many other heavy nuclei emit alpha particles.

Natural radioactivity involving nuclei with mass numbers from 232 to 238 changes them into nuclei with mass numbers from 206 to 208.  The process increases their packing fractions, dissipating energy.  This process usually involves alpha decay.

Nuclei less massive than bismuth-209 usually do not emit alpha particles.  Neodymium-144 is the lightest nucleus that does, but only very slowly.


Beta Decay

Beta decay occurs when a nucleus has too many neutrons for it to remain stable or nearly stable.  In order to reset the imbalance the nucleus must convert one of its neutrons into a proton.  Beta decay achieves this.  The neutron emits a beta particle, which is a negatively charged electron, the neutron then gains a positive charge and becomes a proton.

For example, aluminum-28, with 13 protons and 15 neutrons has too many neutrons to be stable.  So one of its neutrons emits a beta particle and becomes a proton.  This converts the nucleus into silicon-28 with 14 protons and 14 neutrons, which is quite stable.

When a nucleus emits an alpha particle the resultant nucleus is slightly less massive than the mass of the original nucleus and the alpha particle added together.  This difference in mass is accounted for by the kinetic energy of the alpha particle.  This is not quite the situation for beta decay.

When a nucleus emits a beta particle the resultant nucleus should equal the mass of the original nucleus minus the mass of the beta particle minus the kinetic energy of the beta particle.  Usually this is not the case.  Normally the beta particle is moving more slowly than the mass loss indicates.  This would appear to violate the law of conservation of energy.

For many years after beta emission was discovered the cause of the missing energy was unknown.  Then in 1930, Pauli came up with a theory to explain the difference.  He suggested that a second particle was emitted.  In order to conserve charge the new particle must be electrically neutral, which would make detecting it much more difficult.  (Remember that beta decay involves a neutron changing into a proton and emitting an electron therefore conserving charge.  If another particle is emitted it must be neutral.)

The small amount of energy carried off by this new particle is just enough to account for its speed.  Therefore, the particle must have almost no mass.  In 1934, Fermi worked out in detail the properties of the particle and called it the neutrino.


Positron Decay

Positron decay (sometimes called positive beta decay) occurs when a nucleus has too few neutrons for it to remain stable or nearly stable.  In order to reset the imbalance the nucleus must convert one of its protons into a neutron.  Positron decay achieves this.  The proton emits a positron, which is a positively charged electron, the proton then loses its positive charge and becomes a neutron.

For example, aluminum-26, with 13 protons and 13 neutrons has too few neutrons to be stable.  So one of its protons emits a positron and becomes a neutron.  This converts the nucleus into magnesium-26 with 12 protons and 14 neutrons, which is stable.

Positron emission does the opposite of electron (or beta) emission.  In beta emission, the atomic number goes up by one by changing a neutron into a proton, positron emission causes the atomic number to go down by one by changing a proton into a neutron.

Free neutrons decay into less massive protons but free protons do not decay into more massive neutrons.  How then can a proton in a nucleus decay into a neutron?  In a nucleus where protons and neutrons are in close association it is the total mass that counts.  In a nucleus with too few neutrons the total mass can go down if a proton changes into a neutron because the packing fraction increases.  This allows the change to occur.

It is this that makes particular isotopes unstable.  If the total mass of a nucleus is going to decrease if a proton changes into a neutron, or a neutron changes proton, then the change will happen.  If an isotope has a mass that will increase if the change was made, the change will not take place and the isotope will remain stable.  It just so happens that when there are either 43 or 61 protons in a nucleus, no matter how many neutrons are present, changing a proton to a neutron or vice versa will always decrease the mass.  This is why there are no stable isotopes of technetium(43) or promethium(61).

There is one other way that a proton can change to a neutron.  In this process the proton picks up an electron from outside the nucleus.  This is called electron capture.


Electron Capture

Electron capture involves a proton in the nucleus picking up one of the electrons from outside the nucleus.  This neutralizes the electric charge of the proton and converts it into a neutron.  This electron almost always comes from the K shell since it is the shell nearest to the nucleus.  Therefore the process is also called K capture.  It was first observed in 1938 by Luis Alvarez.  However, this process is much less likely to happen than positron emission.


Isomeric Transition

Sometimes when a decay occurs the resulting nucleus is that of a stable isotope but the decay has left the nucleus in an excited state.  Many times this nucleus will then produce Isomeric Transition gamma rays.  This dissipates the excess energy and the nucleus is now more stable.  This does not result in a proton or neutron changing, therefore the nucleus has the same identity but a lower energy state.


Spontaneous Fission

Massive nuclei can undergo another kind of decay although for most it is rare.  This decay is by spontaneous fission.  This is where the nucleus breaks into two lighter nuclei without any energy added from outside.  For example, uranium-238 undergoes 1 spontaneous fission for every 220 times its nuclei simply emit an alpha particle.  Spontaneous fission was first detected by Georgii Flerov in 1941.

Even though it is rare, some radioactive nuclei show a much greater likelihood of undergoing spontaneous fission.  The transuranic isotopes become more unstable not only in ordinary radioactivity but also in the probability of spontaneous fission.  For example, where the spontaneous fission half-life of uranium-238 is about one trillion years, that of curium-242 is 7,200,000 years and californium-250 is only 15,000 years.


Isotopes

Isotope is a term proposed by Frederick Soddy, in 1913, to characterize a nucleus.  It comes from Greek words meaning same place since all isotopes of an element fall into the same place on the periodic table.  It refers to chemical elements that differ from another only by the number of neutrons they posses.  The term nuclide was proposed by Truman Kohman, in 1947, for a species of atom characterized by the number of neutrons and protons the atom contains.  For example, oxygen-15, and oxygen-16 are isotopes of oxygen.  They both have 8 protons but 7 and 8 neutrons respectively.  Whereas, nitrogen-15, oxygen-16, and oxygen-17 are all nuclides.  Nuclide is the more general term.  While isotope can only refer to variations of the same element, nuclide can refer to any element.

Isotopes were first discovered after the invention of the mass spectrograph, developed by Francis Aston.  He was using the instrument to measure the relative mass of atoms of an element.  First the atom is ionized by removing electrons.  This makes the atom positively charged.  The ion is then passed through the mass spectrograph which has magnetic fields at right angles to each other to direct the ions to a photographic plate to that all ions with the same mass are brought to a focus at a fine line.  Heavier ions would be deflected less than lighter ones.

For example, chlorine, whose atomic weight is 35.5, two lines are produced.  One at about mass number 35 and another at about 37.  No lines are found at 35.5.  This confirms that chlorine consists of two isotopes one having mass 35 the other mass 37.  When their natural abundance is taken into account they average out to 35.5.

Most elements in their natural state consists of two or more isotopes.  (20 elements have only one isotope: for example, aluminum, cobalt, and gold.)  Aston proposed a whole-number rule which says that all atomic masses are close to integers and that fractional atomic weights are due to the presence of two or more isotopes each having approximately integral values.

It is now believed that a neutral atom consists of N neutrons, Z protons and Z orbital electrons, and that A(mass) = N+Z.  Isotopes are nuclides with the same Z but different N.


Half-Lives

Half-life is a term introduced by Ernest Rutherford in 1904.  The half-life of a radioactive nuclide is the time it takes for half of the original nuclide to decay into daughter products.  The following discussion will illustrate how this can be determined.

If a given quantity of a radioactive nuclide is observed, it will be seen that over time the number of decay events decline. As the atoms decay there are fewer of the original atoms left to decay, therefore there are fewer decay events to be observed.

The rate that the decay events decline is a property of something called a first-order reaction.  This means that each radioactive nuclide has a certain chance of decaying, and that chance does not change over time.  If it has a one in two chance of decaying today, then if it has not decayed in one hundred days, it still has a one in two chance of decaying on the 101st day.  This is the same as flipping a coin.  You have a one in two chance of getting tails.  Even if you have flipped 10 heads in a row you still have a one in two chance of getting tails on the 11th flip.

You can't tell when any particular atom will decay, but, if you have many atoms, you can calculate how many will decay in one day.  It is just a matter of statistics.  You can't tell which atom will decay but you will know how many atoms will decay.

From this you can calculate how long it will take for half of the atoms to decay.  In the case of first-order reactions, it always takes the same amount time for half of any quantity to decay.  If you have a nuclide with a half-life of one year and you start with 100 grams, then in one year you will have 50 grams of the nuclide.  In another year you will have 25 grams, after three 12.5 grams, after four 6.25 grams, etc.

To determine the half-life of a nuclide, scientists can, in many cases, count the number of alpha or beta particles given off by a nuclide over a period of time.  From the way the count drops off they can calculate the time it would take half of the nuclide to decay.


Interactions

In classical physics the term force was used to describe electromagnetism and gravity.  After the introduction of quantum mechanics, however, it became clear that these "forces" were actually interactions involving exchange particles.  The exchange particles that mediate the interactions are called "gauge bosons".  Below we describe the four interactions.

Electromagnetic Interaction

Hideki Yukawa applied quantum mechanics to the electromagnetic interaction and found that, between charged particles, what was exchanged was photons.  Between particles of the same charge, the exchange produced a repulsion, and between particles of opposite charge, it produced an attraction.  It is an infinite range interaction and its effect declines with the square of the distance.  If you double the distance between particles the interaction's intensity decreases by one fourth.

Gravitational Interaction

The attraction between any two particles of mass is governed by the gravitational interaction.  Any two particles with mass will rapidly exchange gravitons.  Gravitons have not yet been detected because they are so weakly energetic, but scientists do not doubt that they exist.  Since there is only one type of mass, the gravitational interaction produces only an attraction.  It is an infinite range interaction and its effect declines with the square of the distance.  If you double the distance between particles the interaction's intensity decreases by one fourth.

Weak Interaction

This interaction governs the way in which neutrons give off electrons and neutrinos.  It is very short range interaction.  Its range is 10E-15 centimeters or about a thousandth of the width of an atomic nucleus.  It is also very weak.  It is only about a hundred-billionth as intense as the electromagnetic interaction.  It plays almost no role in the nucleus but is important in individual particles.  Baryons, mesons and leptons respond to this interaction.  Events mediated by the weak interaction take place in about a millionth of a second.  It is the only interaction that is not involved in a force of attraction.  It merely mediates the conversion of certain particles into other particles, such as the decay of a pion into a muon, decay of a muon into an electron, or radioactive production of beta particles.

In 1967 a theory by Steven Weinberg, combined the electromagnetic and weak interactions.  His combined interaction was called the electroweak interaction.  It predicted four particles.  One was massless, which was the photon.  The other three had great mass and were called W particles, W+ and W- for the charged particles and Z0 for the neutral one.  In 1983 Carlo Rubbia announced discovery of the W+ and W- particles, and then in 1984, he announced the discovery of the Z0 particle.

Strong Interaction

This interaction is what holds the protons and neutrons together in the nucleus.  It is an extremely short range interaction.  Its range is 10E-18 centimeter or about a hundred-thousandth of the width of an atomic nucleus.  If you double the distance between particles the interaction's intensity drops to less than 1 percent of what it was.

In 1947 Cecil Powel found a particle called the pi meson, or pion.  This is the exchange particle for the strong interaction.  However, while it is a boson it is not a gauge boson.  It is about 273 times as massive as the electron.  It is the rapid exchange of pions in the nucleus of an atom that holds it together.  Both baryons and mesons respond to this interaction.  Leptons do not.  Events mediated by the strong interaction take place in less than a trillionth of a second.

Something must be said here about the pion exchange particle.  As was said it is not a gauge boson.  It is instead a meson.  Mesons are hadrons just as protons and neutrons are hadrons.  Hadrons consists of quarks.  The strong interaction is essentially an interaction between quarks.  Hadrons experience the strong interaction secondarily because they are made up of quarks.  Pions, which seem to be the exchange particle for this secondary hadron interaction, are exchange particles only because they are made up of quarks.  The fundamental strong interaction occurs between quarks.  The exchange particle for the interaction between quarks is a gauge boson, called the gluon.


Subatomic Particles

As physicists probed deeper and deeper into the nucleus the began to find all sorts of strange forms of matter.  Completely new particles were found and studied.  The first of which were mesons, positrons, and muons.  Later whole menageries of particles were found.

As more and more were found scientists started to classify the particles by the quantum properties.

Fermions and Bosons

The highest level of classification was by spin.  The spin quantum number of every particle is always an integer or half-integer.  Particles with half-integer spins behave quite differently from particles that have integer spins.  Particles with half-integer spins are called fermions, in honor of Enrico Fermi, who first described the behavior of this class or particle.  The work on particles with integer spins was done by physicist Satyendra Nath Bose.  These particles are named bosons.  According to this scheme, pions and photons are bosons, while electrons and protons are fermions.

Hadrons

Hadrons are complex particles, in that, unlike leptons, they appear to have internal structure.  They are made up of more fundamental particles called quarks.  Most hadrons are unstable.  Hadrons are subdivided into two groups:  the baryons and the mesons.  Hadrons are affected by the strong interaction.

Baryons

Baryons are fermions.  They are generally heavier than mesons.  They are made up of three quarks.  Protons and neutrons are baryons.  Baryons follow the law of conservation of baryon number.  Baryons are given the baryon number of +1 and antibaryons have a baryon number of -1.

Mesons

Mesons are bosons.  Because of quark color they are made up of two quarks, a quark and an antiquark.  The pion is a meson.  Mesons do not follow the law of conservation of baryon number and are given a baryon number of 0.

Leptons

Leptons are fermions.  The appear to have no internal structure, and no size.  In other words, they appear pointlike.  The are three charged leptons known: the electron, the muon, and the tauon.  They each have a corresponding neutrino: the electron neutrino, the muon neutrino, and the tauon neutrino.  Each one has an anti-particle.  They are not affected by the strong interaction.

Gauge Bosons

The gauge bosons are bosons.  They are all exchange particles and are the mediating particles for the four interactions.  There are four gauge bosons.  The photon, which mediates the electromagnetic interaction.  The W particles, which mediate the weak interaction.  The graviton, which mediates the gravitational interaction.  The fourth is the gluon, which mediates the strong color interaction whose by-product is the strong interaction.  They are all point-like particles, and therefore show no structure.


Quarks

By the late 1950's there were hundreds of hadrons that had been discovered.  It seemed that instead of simplifying matters, things were getting more complicated.  Something was needed to put order to the growing hadron zoo.

There were two classes of hadrons.  First was the baryons, which were classed as fermions or hadrons with half-integer spins.  The other was the mesons or hadrons with integer spins.  But the classifying of hadrons into baryons and mesons was not enough.

In 1961, Murry Gell-Mann tried to do with hadrons what Mendeleev had done with elements by grouping the hadrons by their characteristics.  This proved to be very successful as each of the hadrons began to fit into its own family.  For example, the proton and neutron are members of a family of 8 hadrons.  The other members of the family are the lambda, the three sigma, and the two xi particles.

In 1962 Gell-Mann used his theory to predict the existence of an undiscovered particle which he called the omega minus particle.  It was to be the tenth member of a ten member family.  By 1953 the particle had been found, giving further validity to the theory.

But just as the periodic table was first presented, no one knew why Gell-Mann's theory was so successful.  What made the hadrons fit so well into these groups?  Many scientists believed that hadrons were elementary particles.  But if they were why did it seem that there was an unlimited number of them?

Gell-Mann believed that there had to be an internal structure to hadrons that would allow them to be grouped.  This was not an unbelievable idea, since leptons acted as though they were point-like hadrons did not.  So he started to make up a group of particles that would be fundamental, such that when put together properly they would form all the hadrons with their various properties.  However, he quickly found that in order to do this his new particles must have fractional charges.  To Gell-Mann this seemed improbable.  Since the days of Faraday everything had been in multiples of a single charge, that of the electron.

He decided to publish anyway in 1963.  He said that there would be three fundamental particles and their three antiparticles.  He called the particles quarks.  Baryons would contain three and mesons would contain two particles which are always a quark and an antiquark.

The three types, or flavors, of quarks were called the up quark, down quark and the strange quark or the u, d and s quarks.  The u quark has a charge of +2/3, the d quark of -1/3 and the s quark -1/3.  Each quark also has a series of numbers representing various characteristics it conserves.  The quarks must be put together such that the hadron has they form has all of the various numbers associated with its characteristics.  They must also be put together such that the hadron will have a charge of -1, +1 or 0.

For example, a proton is two u quarks and one d quark, with a total charge of +2/3 and +2/3 and -1/3 or +1.  A neutron is built of one u quark and two d quarks (+2/3 and -1/3 and -1/3), for a total charge of 0.  A positive pion is built from a u quark and a d antiquark (+2/3 and +1/3).

The s quark goes into building the strange particles, which is what gave the s quark its name.  It has a charge of -1/3 and a strangeness number of -1 the s antiquark has a charge of +1/3 and a strangeness number of +1.  The positive Κ meson , or kaon, contains a u quark and an s antiquark, for a total charge of +1 and a strangeness number of +1.  The negative Κ meson contains a u antiquark and an s quark for a charge of -1 and a strangeness number of -1.

Later, other more massive particles than the pion or kaon were found that did not fit the quark model with the current quarks.  It was theorized and later confirmed experimentally that they contained new flavors of quarks which were the charm or c quark, the bottom or b quark, and the top or t quark.  Now with six quarks scientists can describe all hadron found so far.

Are there more quarks?  As physicists are able to create more massive hadrons will new quarks be found?  No one knows for sure.  But as particle accelerators become more powerful physicists feel that they are coming closer to a truly fundamental particle.

Even though particle accelerators have become more powerful why have we not seen a free quark.  Surely if we were to smash a proton and neutron together with enough force we would break them open and find free quarks.  And if we can't find them outside a hadron are they really there?  What holds them together so tightly?  Much of this is explained by a theory called quantum chromodynamics.

Scientists at Stanford set up an experiment to try to detect quarks.  The sent a beam of high energy electrons through a tank of liquid hydrogen.  Many of the electrons went through the hydrogen without hitting anything.  But a number of them changed direction in a way that indicated that they had hit something within the proton in the hydrogen nucleus.  Here was the first direct evidence that protons were not fundamental particles but, instead, had an internal structure.


Quantum Chromodynamics

Why are the quarks so tightly bound inside a hadron?  By the early 1970's physicists had a theory suggesting a new interaction.  It proposed a new property of matter called "color".  Particles such as quarks, it was proposed, had a color property and reacted to this new interaction, called the strong color interaction.  The word color in this name is used to distinguish it from the strong nuclear interaction which hold hadrons together.

The use of the word color should not be confused with what we know as color.  It is just a convenient term to describe how the interaction works.  Quarks come in three types, red, green and blue.  A combination of each results in an absence of color or whiteness.  Every quark combination in hadrons must produce a white result.

Each flavor of quark and antiquark comes in each of the three colors.  For example, in the case of the u (or up) quark, there is a blue u quark, a red u quark, and a green u quark.  There is an anti-blue anti-u quark, an anti-red anti-u quark and an anti-green anti-u quark.  In other words in this new theory there are 18 kinds of quarks and 18 antiquarks.

Like real colors, certain combinations of either quark or antiquark colors produce a white, or neutral, result.  These combinations are the only ones possible that will produce a hadron.  At any instant in a proton, for example,  the three quarks will all be a different color.  It doesn't matter which color the proton's d (or down) quark is as long as the result is neutral.  In the case of a meson this is why one quark must always be an antiquark.  Green with anti-green, or red with anti-red always produces white.

This explains why there are three quarks to every baryon and a quark/antiquark pair in every meson.  These are the only combinations which are colorless.  The development of the color theory explained a number of observations that had been anomalous without it.

It was seen that there must be some exchange particle that would account for the strong color interaction.  Gell-Mann named it the gluon, another gauge boson.  It was the gluon that carried the color property.  It had the ability to change the color of quark but not its flavor.


Gluons

Gluons, so named because they are the glue that holds quarks together, were proposed by Gell-Mann.  They have properties that are quite different from other gauge bosons.  Like a photon it has no mass and its electric charge is zero.  It moves at the speed of light and like all bosons has a whole integer spin, which is +1.  But unlike other gauge bosons, gluons have the same property that they mediate, namely color.

For example, gravitons are exchanged by particles that have mass, but have no mass themselves.  Photons are exchanged by particles with electric charge, but have no charge themselves.  Gluons, which have color, are exchanged by particles that have color.  Therefore gluons can stick to each other.  (A pair of gluons that stick together is called a glue ball.)

But, where each quark has only one color at a time each of the eight types of gluons always have two colors.  These colors need not be complimentary as do mesons.  For example, you could have a blue-anti-red gluon.

Quarks are constantly exchanging gluons, and in doing so are constantly changing their colors.  For example, a blue u quark may emit a blue-anti-red gluon and be changed into a red u quark.  The red d quark that might absorb this gluon will become a blue d quark.  So you see, the flavor of the quark does not change only the color.  Therefore the overall color of the hadron remains neutral also even though the quarks did change color.

According to quantum chromodynamics, or QCD, the exchange of gluons between quarks prevents them from breaking free of the hadron.  Other boson exchanges also keep particles together, but their effects diminish when the distance between particles increases.  This the opposite of what happens when gluons are exchanged.  As the distance between quarks increases the number of gluons exchanged increases, which has the effect of increasing the attractive force between the quarks.  This is one of the effects of the gluons color charge, called quark confinement, and it explains why quarks have never been seen or isolated.

Quark confinement can be mathematically defined but any attempt to describe it in ordinary language will never represent the true picture because no one can really visualize it.  This is true of other quantum phenomena as well.  But, some models have been expressed that give some idea about what is happening.

One is called the bag model.  In this model hadrons are pictured as tiny bags which contain quarks.  When two hadron bags collide in an attempt to break them open, the two bags instead momentarily form one large bag that contains all the quark from both hadron bags.  The quarks are then jumbled up and then the bag breaks into two or more bags.  Each new bag will be a hadron with its quarks still confined as before, although they may be different quarks.

Another model is called the string model.  It pictures quarks within a hadron as being attached to each other with strings.  If the quarks are close to each other, the strings are slack and the quarks move about freely.  But if they are pulled away from each other the strings become taut and the quark's motion is rigidly controlled.  The greater the pull on the strings the more tightly the strings hold the quarks.


Neutrinos

In 1934, Fermi worked out in detail the properties of the neutrino.  He believed it to be a particle with no mass, no electric charge, and virtually no tendency to interact with matter.  It was a nothing particle.  It might as well have been so except that it conserved several conservation laws that seemed to be violated during beta emission.

If a motionless neutron is allowed to decay into a proton and an electron, the electron will go flying off in some direction at great speed and therefore have a sizable momentum.  The proton (formerly the neutron) will recoil in the opposite direction at a lesser speed but greater mass.  The momentum of the electron (small mass × high velocity) should be equal to the momentum of the proton (high mass × low velocity).  If they go off in opposite directions, one will have a momentum of +x, the other -x which will work out to a momentum change of 0.  Therefore the law of conservation of momentum is conserved.  Unfortunately this is not what happens.  However, if a neutrino is also emitted, it can account for the missing momentum.

Consider also that the neutron has a spin of either +½ or -½.  If only a proton and an electron were emitted there would be an imbalance in spin.  A proton has a spin of +½ or -½ as does an electron.  Therefore the total spin after the breakdown could be +1, -1, or 0.  This means that the law of conservation of angular momentum would be broken.  But, if the neutron also ejects a neutrino, which also has a spin of +½ or -½ then the total after the breakdown can add to +½ or -½ which is the spin of the original neutron, therefore conserving angular momentum.

There is another law of conservation that must also be conserved: the law of conservation of lepton number.  The neutron and proton both have a lepton number of 0 (since they are baryons).  The electron has a lepton number of +1 or -1, depending on the charge of the electron.  (An electron has charge -1 and lepton number +1, a positron has a charge of +1 and a lepton number of -1.)  The neutron, then, starts off with a baryon number of +1 and a lepton number of 0.  When it breaks down, the proton has a baryon number of +1 and lepton number of 0 and the electron has a baryon number of 0 and a lepton number of +1, the baryon number is conserved but the lepton number is not.  But, if a neutrino is formed with a lepton number of -1 and baryon number of 0, you have now conserved lepton number since you started with a neutron with baryon number +1 and lepton number 0 and formed three particles that total to baryon number +1 and lepton number of 0.

A normal neutrino has a lepton number of +1, which would not work for the above breakdown. The -1 lepton number of the neutrino actually makes it a mirror particle (or antineutrino) but this is fine, since an antineutrino conserves the laws of energy, charge, momentum, angular momentum, and lepton number just as well as a neutrino.

The detection of the neutrino took many years because it is exceedingly difficult to detect.  It is calculated that a neutrino can pass through 3,500 light-years of solid lead before being absorbed.  Of course, this is the average neutrino.  Individual neutrinos might pass twice that far or only a millionth as far before being absorbed.  This means that if you could produce a stream of trillions of trillions of neutrinos in a lab, a few just might happen to hit some particle and interact.

Just such a source is available: nuclear reactors.  How are they produced?  Uranium-235, which is used in many reactors, with its 92 protons requires 143 neutrons to keep its nucleus nearly stable.  When the nucleus fissions into smaller nuclei, each requires fewer neutrons to be stable.  This sets some neutrons free.  Over a period of time these neutrons break down into protons and electrons producing antineutrinos as well.  A typical reactor could produce a billion billion antineutrinos every second.

With a source of antineutrinos, the next thing to do was to decide what the antineutrino would do.  Consider what would happen if an antineutrino hit a proton.  If an antineutrino hits a proton, the proton will emit a positron and change into a neutron.  Note that this process conserves the law of baryon number, proton +1 and neutron +1.  It also conserves lepton number, antineutrino -1, positron -1.  It conserves electric charge, proton +1, positron +1.  The other conservation laws are also conserved.

The interaction can be detected because the positron that is emitted will strike an electron within a millionth of a second and they will mutually annihilate each other.  The process produces two gamma rays of equal strength moving in opposite directions.  The neutron produced in the antineutrino reaction could be absorbed by a cadmium atom which will produce gain energy and emit three or four photons of a fixed energy.

Finally, in 1956, Fredrick Reines and Clyde Cowan created a detector made up of a tank of water (lots of protons in the water molecules) with some cadmium chloride to absorb any neutrons produced.  Then they added devices to detect the gamma rays, their directions, and their energies.  Then they waited for the occasional antineutrino to interact with a proton, which they found.  It was 26 years after Pauli suggested the existence of the neutrino.


No Help Available

No help is available for this area of the window.


No Help Available

No help is available for this message box.


The percentage that any particular natural isotope occurs in a sample of an element.


A machine that increases the velocity of charged particles, thus imparting great energies to them.


A compound that reacts as a weak acid or a weak base.


The process that occurs when a particle and an antiparticle meet and their masses are converted into energy in the form of gamma rays.


For every subatomic particle there is an antiparticle of equal mass but opposite electric charge; for neutral particles such as the neutron and neutrino, the antiparticle has some other opposite property to distinguish it.


Atomic number is an experimentally determined number characteristic of a chemical element that represents the number of protons in the nucleus which in a neutral atom equals the number of electrons outside the nucleus.


Measured in angstroms, it is based upon interatomic distances in the solid state.


Atomic volume is the volume occupied by one mole (mol) of atoms of an element.  A mole is defined as the gram-formula weight of a substance.  The formula weight of a substance is the sum of the atomic weights of the atoms that make up the molecule.  For example, sulfuric acid has a formula weight of 98.1.  If you had 98.1 grams of sulfuric acid you would have one mole of sulfuric acid.


The atomic weight, or mass, of an element is the average relative weight of an element referred to carbon 12 as a standard.


Hadrons such as protons and neutrons that have half-integer spin values and are composed of three quarks.


Particles, such as the photon and mesons, that have whole integer spin values.


The Windows clipboard allow you to copy information there from one application and paste that information into another application.


The ability to form a bond in which two atoms share a pair of electrons.


Covalent radius is the internuclear distance between atoms in a molecule.  Covalent bond lengths may be assigned to pairs of atoms with similar bonds.  That is, it is one half the distance between the center of the two atoms that are covalently bonded.  Covalent radius is also known as bond length.


The transformation of subatomic particles into more stable particles; also the transformation of radioactive elements into other elements.


The mass of a substance per unit volume; for example, how many atoms an object has per cubic centimeter.


A substance is ductile if it can be hammered out thin or drawn into a wire.


The ability of a substance to pass electrons in the form of an electrical current.


An elementary particle that is negatively charged.  It is one of the three major particles found in a normal atom and was the first elementary particle to be discovered.  It is a lepton.


The tendency to gain electrons; nonmetallic; acid.


A measure of the attraction of an atom for electrons in its outer shell.


The tendency to lose electrons; metallic; basic.


Any one of the many bands that electrons may occupy in an atom.  Only a certain number of electrons may be in any one shell at a given moment.


A substance consisting entirely of atoms of the same atomic number; a substance that can be combined with other elements to form compounds but that cannot be broken down into any simpler substance once it is separated out of a compound.


Any particle with a half-integer spin value such as the electron, proton, and neutron.


Particles with integer spin values whose exchanges generate the interactions between other particles.


The group of an element is its horizontal position on the table.


Halogen means salt producer.  Sea salts are compounds of halogens with metals.


The heat energy that must be supplied to evaporate a unit mass of liquid at a constant temperature.


The quantity of heat that must be supplied to change a unit mass of a substance from the solid to the liquid state at a constant temperature.


Any particle that participates in the strong interaction.


Any compound consisting of an element or radical combined with one or more hydroxyl radicals (OH - one oxygen atom combined with one hydrogen atom).


First - The amount of energy required to remove the most loosely bound electron from an atom.  Similarly for second and third - The amount of energy required to remove the second or third most loosely bound electron from an atom.


A fundamental property of subatomic particles describing the state of rotation of the particle.


Two or more species of atoms having the same atomic number (number of protons) but with differing atomic mass number (number of protons and neutrons).  In other words they will differ in the number of neutrons in the nucleus.  Isotopes have nearly the same chemical properties but may differ in physical properties.


Elementary particles with half-integer spin values that participate in the weak and electromagnetic interactions but not in the strong interaction.


A hadron with an integer spin value composed of a quark and an antiquark; examples are pions and kaons.


A nuclide which has just decayed may be in an excited state.  This state is called a metastable state.  The excited nuclide will then experience another decay event which may eventually result in the nuclide reaching the ground state.


Monoatomic means it occurs as single atoms rather than in pairs or combination.


An elementary particle, one of the leptons, with a mass more than two hundred times that of the electron.  It is also called the mu-meson.


An electrically neutral particle, a baryon, that is a constituent of all atomic nuclei except hydrogen-1.


The positively charged core of an atom; consists of one or more protons and, except for hydrogen-1, two or more neutrons.


The term nuclide was proposed by Truman Kohman, in 1947, for a species of atom characterized by the number of neutrons and protons the atom contains.  For example, oxygen-15, and oxygen-16 are isotopes of oxygen.  They both have 8 protons but 7 and 8 neutrons respectively.  Whereas, nitrogen-15, oxygen-16, and oxygen-17 are all nuclides.  Nuclide is the more general term.  While isotope can only refer to variations of the same element, nuclide can refer to any element.


The packing fraction of a nucleus is the difference between the actual mass of the nucleus and the sum of the protons and neutrons in the nucleus.

For example, carbon-12 has 6 protons and 6 neutrons in its nucleus. If we add up the mass of 6 protons and 6 neutrons we get 12.09606. But the actual mass of carbon-12 is 12.00006 or 0.096 lighter. This 0.096 mass defect is then divided by 12 to get 0.008. Then to avoid working with small numers you multiply the 0.008 by 10,000 which gives carbon-12 a packing fraction of 80.


Each horizontal row in the Periodic Table is called a period.  Each period begins filling a new electron shell.


An elementary particle whose exchange generates the electromagnetic interaction between charged particles; a quantum of electromagnetic radiation.


The massive particle, about two hundred seventy times as massive a the electron, whose exchange generates the strong nuclear interaction between hadrons.


The positively charged antiparticle of the electron.


A positively charged baryon found in all nuclei of normal atoms.


The state of an element in a compound with respect to the number of electrons it has lost or gained, expressed as a positive or negative number indicating the ionic charge of the atom and equal to its valence.


Change the atoms or ions of an element to a higher positive valence by the loss of electrons.  An oxidizing agent is an element that can remove electrons from another element.


Change the atoms or ions of an element to a lower positive valence by the gain of electrons.  A reducing agent is an element that can add electrons to another element.


The number of calories of heat required to raise the temperature of one gram of the substance one degree.


The atomic symbol of an element is its one to three letter abbreviation.  For example, H is the symbol for hydrogen and Pb is the symbol for lead.


The ability of a substance to transfer heat energy from one atom to another.


The electrons in the outermost shell of an atom are called its valence electrons.


File Print command
Print command (File menu)

Use this command to print a report.   This command presents a Print dialog box, where you may specify the range of pages to be printed, the number of copies, the destination printer, and other printer setup options.

Shortcuts

Toolbar:

Keys:	CTRL+P


Print dialog box

The following options allow you to specify how the report should be printed:

Printer

This is the active printer and printer connection.  Choose the Setup option to change the printer and printer connection.

Setup

Displays a Print Setup dialog box, so  you can select a printer and printer connection.

Print Range

Specify the pages you want to print:

All	Prints the entire report.
Pages	Prints the range of pages you specify in the From and To boxes.
Copies

Specify the number of copies you want to print for the above page range.

Collate Copies

Prints copies in page number order, instead of separated multiple copies of each page.  May not be available for all printers.

Print Quality

Select the quality of the printing.  Generally, lower quality printing takes less time to produce.


Print Progress Dialog

The Printing dialog box is shown during the time that Periodic Table is sending output to the printer.  The page number indicates the progress of the printing.

To abort printing, choose Cancel.


File Print Preview command
Print Preview command (File menu)

Use this command to display the active report as it would appear when printed.  When you choose this command, the main window will be replaced with a print preview window in which one or two pages will be displayed in their printed format.  The print preview toolbar offers you options to view either one or two pages at a time, move back and forth through the report, zoom in and out of pages, and initiate a print job.

 Print Preview button


Print Preview toolbar

The print preview toolbar offers you the following options:

Print

Bring up the print dialog box, to start a print job.

Next Page

Preview the next printed page.

Prev Page

Preview the previous printed page.

One Page / Two Page

Preview one or two printed pages at a time.

Zoom In

Take a closer look at the printed page.

Zoom Out

Take a larger look at the printed page.

Close

Return from print preview to the editing window.


File Print Setup command
Print Setup command (File menu)

Use this command to select a printer and a printer connection.  This command presents a Print Setup dialog box, where you specify the printer and its connection.


Print Setup dialog box

The following options allow you to select the destination printer and its connection.  Some of these options are printer dependent and will not be available for all printers.

Printer

Select the printer you want to use.  Choose the Default Printer; or choose the Specific Printer option and select one of the current installed printers shown in the box.  You install printers and configure ports using the Windows Control Panel.

Orientation

Choose Portrait or Landscape.

Paper Size

Select the size of paper that the document is to be printed on.

Paper Source

Some printers offer multiple trays for different paper sources.  Specify the tray here.

Options

Displays a dialog box where you can make additional choices about printing, specific to the type of printer you have selected.

Network...

Choose this button to connect to a network location, assigning it a new drive letter.