c) (10 points) Compressed propane has been suggested as an alternative fuel for motor vehicles because it generates lower levels of pollutants. In a test, 0.46 moles of C3H8 was burned with 13.8 moles of air to produce 1 mol of CO2 and 1 mol of CO. What was the percent excess air used in this test

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.