Final answer:
To determine the heat capacity of a calorimeter, a known mass of benzoic acid is combusted and the temperature increase of the calorimeter is measured to calculate the heat capacity using the measured qrxn and ΔT.
Step-by-step explanation:
To calculate the heat capacity of a calorimeter during the combustion of benzoic acid, we must first carry out a calibration process using benzoic acid as a standard because its enthalpy of combustion is well-known. The process involves burning a meticulously measured amount of benzoic acid within the bomb calorimeter, leading to a specific heat release (26.38 kJ per gram for benzoic acid). The corresponding temperature rise in the calorimeter is then recorded.
The formula qrxn = m×ΔHcomb is used to calculate the heat evolved from the reaction (qrxn), where 'm' is the mass of the benzoic acid and ΔHcomb is the enthalpy of combustion per unit mass. The calculated qrxn and the observed temperature change (ΔT) in the calorimeter are then put into the equation Cbomb = qrxn / ΔT to find the calorimeter's specific heat capacity (Cbomb).