Regarding Chemicals and Gases in the air…What does different color fire mean?
Different elements give off different colors when burned. If the fire changes color it is because a particular element is being burned. Its called the flame test. Lithium is red, coppers are blue or green. This is due to the electrons gaining energy and being excited to higher energy levels then falling (relaxing) back to the ground state by emitting the particular energy that it takes to get from the excited state level back down. It just so happens that in some cases the energy release corresponds to the visible light region. Just enough energy to be red, green, blue etc. Since wavelength can be related to energy nicely we can know exactly how much energy it has released.
