A scale uses the principle of. to measure how much something weighs

1000/2 = 500 gallons of C8H18         500*6 = 3000 pounds of C8H18          3000/2.2 = 1363.6363 ≈ 1364 kg of C8H18 = 1364000 g C8H18           C8H18 + O2 ---> 8CO2 + H2O   (ignore the incorrect coefficients for O2 and H2O I'm not bothered)             Mr of C8H18 = 114             1364000/114 ≈ 11965 mol C8H18          ≈11965*8(from equation) = 95719 mol CO2             Mr CO2 = 44            95719*44 = 4211649 g of CO2            4211649/1000 = 4211.65 kg CO2