In an auto engine with no pollution controls, about 5% of the fuel (C8H18) is unburned. Molar ratio of CO and C8H18 emitted in the exhaust gas is

C8H18+8.5O2⟶8CO+9H2O 1 mol                     8 mol           0.95 mol               7.6 mol    Emitted gas contains 0.05 mol C8H18 and 7.6 mol of CO if 1 mole of C8H18 is the fuel.∴ COC8H18=7.60.05=152