Posted by emily on .
if you combust 30kg of octane (about the amount in one tank for a small car), how many kilograms of CO2 will you emit?

chemistry 
MathMate,
Octane has a chemical formula of C8H18.
For complete combustion, the reaction is:
2C8H18 + 25O2 > 16CO2 + 18H2O + heat
RMM(C8H18)=114
RMM(CO2) = 44
So 2*114 grams of Octane will produce 16*44 grams of CO2.
Can you take it from here?
Check my calculations.