Carbon monoxide at 1000C and atmospheric pressure is burnt with 100% excess dry air at 2000C. The products of combustion leave the reaction chamber at 8000C. Calculate the heat evolved in the reaction chamber in kcal/kmol of CO burnt assuming complete combustion. Standard heat of combustion of CO is -67.636 kcal/kmol. Mean heat capacities of CO, air, carbon dioxide, oxygen and nitrogen are 7.02, 7.23, 11.92, 7.94 and 7.06 kcal/kmol respectively.