Calorimetry is the experimental process of studying the conservation of heat energy in closed systems. According to the laws of thermodynamics, when matter is transformed through chemical or physical reactions, energy is released as heat or work. Calorimetry provides a measurement of the released heat.

For example, imagine the steam from a kettle operating a small paddlewheel. Some of the heat is retained by the water in the kettle and the escaping steam, some is absorbed by the surrounding air from the steam, and some is translated into the work necessary to move the paddlewheel. If you could measure the heat in the water and the heat absorbed by the air, you would find the sum of all the heat equaled the energy invested (supposedly by the stove) plus the energy transformed into work. Still, how could you measure the energy from all those sources? In the natural...