Question

A major component of gasoline is octane (C8H18). When octane is burned in air it chemically reacts with oxygen (O2) to produce carbon dioxide (CO2) and water (H2O). What mass of oxygen gas is consumed by the reaction of 8.17g of octane?.

Answer 1

balance the equation:
2C8H18+25O2 >>>16CO2 + 18H2O

So for each mole of Octane you burn, you need 12.5 moles of O2

figure out the moles of octane you used, then multiply it by 12.5.
then, multiply that by 32 to get the grams of O2

Answer 2

24.2