(a) A bomb calorimeter was calibrated by igniting a 0.825 g sample of benzoic acid in the presence of excess oxygen. The heat given out made the temperature of the calorimeter rise by 1.940 K from 298 K. The internal energy of combustion of benzoic acid is -3251 kJ mol-1. Calculate the heat capacity of the calorimeter. (b) In two separate experiments in the same apparatus, 0.498 g of fumaric and 0.509 g of maleic acid were ignited and gave temperature rises of 0.507 K and 0.528 K respectively. Use the heat capacity of the calorimeter, calculated in (a), to calculate a. the molar internal energy of combustion, b. the molar enthalpy of combustion, and c. the molar enthalpy of formation of fumaric and maleic acids. Comment on the difference. The standard enthalpy of formation of water is -285.8 kJ mol-1 and of CO2 -393.5 kJ mol-1.