Bomb Calorimeter
A rigid sealed vessel used to measure the heat released by combustion at constant volume.
Formula / equation
q_V = ΔU
Unit
J
In depth
The sample is ignited electrically in excess oxygen at high pressure inside a steel bomb immersed in water. Because the volume is fixed, no expansion work is done and the measured heat equals the internal energy change, which is converted to enthalpy by adding Δn_gasRT.
Examples in the real world
Determining the calorific value of a foodstuff or the energy density of a new fuel.