Confidence votes 18.4K. It depends on the amount of gasoline and its composition; gasoline is not a compound with a fixed proportion between elements, but rather a mixture. If the questioner means the normal range of carbon atoms per molecule in gasoline, this is usually considered to be from 6 to 10.he carbon atom has 15 known isotopes, all of which vary in the  number of neutrons. The most common isotope, carbon-12 has 6  neutrons.