Principle of Calorimetry:

When two bodies of different temperatures are brought in thermal contact then reception and donation of heat take place. The body at higher temperature leaves heat whereas the body at lower temperature receives heat. This give and take will continue until they reach at the thermal equilibrium.

If no heat is lost during donation and reception of heat, then the amount of heat given up by the body at higher temperature will be equal to the heat gained by the body at lower temperature.

So, Heat lost = Heat gained

It is called the principle of Calorimetry.


Key points of Calorimetry:

  • Calorimetry is the science of measuring the heat of chemical reactions or physical changes. It involves measurements made with calorimeters.
  • The heat of the reaction is the negative of the amount of heat gained by the calorimeter. The calorimeter may be made of more than one component, such as a bomb and a water bath.
  • The amount of heat gained by the calorimeter is also a product of the heat capacity of the calorimeter and the change in temperature of the sample undergoing a chemical or physical change.