C weighs 12 O weighs 16 And there's two Os in a molecule of CO2, and gas is mostly a bunch of Cs. The Os come from the air. (and it's 20 pounds per gallon,

C weighs 12 O weighs 16 And there's two Os in a molecule of CO2, and gas is mostly a bunch of Cs. The Os come from the air. (and it's 20 pounds per gallon, not mile)