An automobile burns 65 grams of gasoline over 20 minutes. The gasoline combines with 100 grams of oxygen in this reaction, to form carbon dioxide and 47 grams of water. How much carbon dioxide is formed?

do I use the heat capacity equation?

How much oxyen is used to produce 47 g H2O?
47g/18 = ?? mols H2O
mols O = Mols H2O = xx
mols oxyen x 16 =yy g oxygen.

100 g oxygen - g used to produce H2O = g used to produce CO2.
Convert g used to produce CO2 to mols O and then to g CO2.
Check my thinking. About 80 g CO2 estimate.