What are thermochemical reaction and their types?

Thermochemical reactions are chemical reactions that involve the absorption or release of heat energy, resulting in changes in enthalpy. These reactions can be classified into two main types: exothermic reactions, which release heat to the surroundings (e.g., combustion), and endothermic reactions, which absorb heat from the surroundings (e.g., photosynthesis). Additionally, thermochemical equations often include the enthalpy change (ΔH) associated with the reaction, providing insights into the energy dynamics involved.