Question

If a car produces 88g of CO2, how many grams of O2 are used up in the reaction?

Answer 1

If you work this the easy way you don't get the right answer. The easy way is to convert CO2 to O2; however, remember that a car using a hydrocarbon for gasoline and that produces CO2 AND H2O, both which contain oxygen. I think you need know what hydrocarbon is being burned. Then write the equation and follow the steps of this link below.
http://www.jiskha.com/science/chemistry/stoichiometry.html