Calculating Heat from Bomb Calorimetry

Calculating heat from bomb calorimetry means adding the heat absorbed by the surrounding water to the heat absorbed by the bomb itself, since both together make up the calorimeter's full surroundings.

Burning 3.12 g of glucose inside a bomb calorimeter containing 775 g of water raises the temperature from 23.8 °C to 35.6 °C, and the steel bomb's own known heat capacity is 893 J/°C. Multiplying the water's mass, specific heat, and temperature change gives the water's heat gain; multiplying the bomb's heat capacity by that same temperature change gives the bomb's own heat gain. Adding these two contributions together gives a total heat release near 48.7 kJ for that single glucose sample.