The calorimeter contained 500 g of water and the temperature rise measured was 1.40 degrees Celsius. A sample of magnesium metal (0.1946 g) was ignited in a constant-volume calorimeter of heat capacity 1349 J/g degrees Celsius.
Determine the heat of combustion of magnesium metal in kJ/g where the specific heat of water = 4.184 J/g degrees Celsius.