Bomb Calorimeter Used to measure enthalpy changes of combustion reactions at a constant volume Occurs inside a tiny inner metal chamber called a bomb The bomb contains pure oxygen, the reactants are ignited using an electric coil A known quantity of water surrounds the bomb and absorbs energy that is released by the reaction

Bomb Calorimetry To obtain precise heat measurements, you must know or find out the heat capacity of the bomb calorimeter Heat capacity takes into account all the parts of the calorimeter that can lose or gain. c total = c water + c thermometer + c stirrer + c container

Bomb Calorimetry Since mass of the other parts are constant, there is no need for the mass units in the heat capacity value. Manufacturers include the heat capacity (C) of a calorimeter when it is purchased. Therefore, q cal = CΔT C= heat capacity of the calorimeter