exothermisyys

Exothermisyys refers to the property of a chemical reaction or process that releases energy, typically in the form of heat, into its surroundings. This release of energy causes the temperature of the surroundings to increase. In an exothermic reaction, the energy content of the products is lower than that of the reactants. The difference in energy is liberated as heat.

The term "exothermic" is derived from Greek roots: "exo" meaning outside, and "thermos" meaning heat. Therefore, an exothermic process is one that gives heat "outside" or to the environment. Common examples of exothermic reactions include combustion, such as burning wood or natural gas, and neutralization reactions between strong acids and bases. The formation of many chemical bonds is also an exothermic process, as energy is released when stable bonds are formed.

Conversely, processes that absorb energy from their surroundings are called endothermic. In these cases, the temperature of the surroundings decreases. Exothermic reactions are characterized by a negative change in enthalpy (ΔH < 0), indicating that heat is released. This energy release is a fundamental aspect of thermodynamics and plays a crucial role in various natural phenomena and industrial applications, from power generation to chemical synthesis. Understanding exothermicity is essential for controlling reaction rates, managing heat flow, and ensuring safety in chemical processes.