Transcription: This experiment demonstrates how important concentration is in determining a chemical's behavior. What you're seeing here is a paint can that has been filled with methane. You call it natural gas. That methane has been ignited so a pleasant blue flame comes out the hole in the top of the can. Now this is actually a chemical reaction in which methane, CH4, reacts with oxygen, O2, to make carbon dioxide, CO2, and water, H2O. Now, if you don't understand that chemical equation, don't worry about it. The important thing is it's a chemical reaction between methane and oxygen. Now, as long as the co ...