Combustion is principally the oxidation of carbon in compounds by oxygen in air to carbon dioxide, carbon monoxide, or carbon itself. Combustion produces not only CO 2 and H 2 O, but also heat. The energy contained in the bonds of the products is less than the energy contained in the bonds of the reactants. The difference in energy is released as heat. Energy releasing reactions are called exothermic Calorimetry is a way to determine the amount of heat released in a reaction.
Calorimeters are devices to measure heat released by a reaction.
The temperature of the calorimeter increases as heat is released by a reaction. This temperature can be easily measured. But there has to be some way to relate the temperature change to heat. The connecting link is the heat capacity of the calorimeter, C p . If we know C p , then we can use this equation to connect the measured temperature change to the amount of heat energy that caused the temperature change.