Answer to Question #54990 in General Chemistry for michelle

Question

if i have 100g of coal, 100g of petrol and 100g of wood how much energy (kj) would i get from each?

Answer 1

If you will use the following values of heat of combustion: petrol 45.58 MJ/kg, coal 25.58 MJ/kg and wood 21.14 MJ/kg, you will get the folloving results petrol 4558 kJ, coal 2558 kJ and wood 2114 kJ.
Calculation:
Heat = Heat of combustion*Weight
petrol Heat = 0.1 kg*45.58 MJ/kg = 4558 kJ
coal Heat = 0.1 kg*25.58 MJ/kg = 2558 kJ
wood Heat = 0.1 kg*21.14 MJ/kg = 2114 kJ