calorimètres

A calorimeter is a device used to measure the heat of chemical reactions or physical changes. It operates on the principle of conservation of energy, where heat lost by a system is gained by its surroundings, or vice versa. The core of a calorimeter is typically a well-insulated container that prevents heat exchange with the external environment. Inside this container, a known mass of a substance, often water, is heated or cooled by the process being studied. By measuring the temperature change of the substance and knowing its specific heat capacity, the amount of heat transferred can be calculated.

There are several types of calorimeters, each suited for different applications. Bomb calorimeters are commonly used for combustion reactions, where a substance is burned in a sealed, high-pressure vessel. Solution calorimeters are used for reactions that occur in solution. Adiabatic calorimeters are designed to minimize heat exchange to the point where the process itself generates negligible heat, allowing for precise measurements. Calorimetry is a fundamental technique in chemistry and physics, used in fields ranging from materials science and engineering to food analysis and biological research to determine the energy content of fuels, the enthalpy of reactions, and the thermodynamic properties of substances.