A calorimeter is a scientific instrument used to measure the amount of heat involved in a chemical reaction or physical change. It helps determine the energy changes that occur during these processes, which is essential in fields like chemistry, biology, and physics. Calorimeters can be simple, like a coffee cup calorimeter, or more complex, like a bomb calorimeter, depending on the precision required. In a calorimeter, a sample is placed in a controlled environment, often surrounded by water or another substance. As the sample undergoes a reaction, it either absorbs or releases heat, causing a temperature change in the surrounding medium. By measuring this temperature change, scientists can calculate the energy involved, providing valuable insights into the properties of the material being studied.