0Endothermic reaction : Any chemical reaction that absorbs heat from the environment is termed as an endothermic reaction. The absorbed energy provides the activation energy for the reaction to occur.
Example : Mixing water ( H2O ) with Potassium Chloride ( KCl ) is an example of endothermic reaction.
Photosynthesis is also an example of endothermic reaction. Here Chrolophyll is used from sunlight to react water and carbon dioxide ( CO2 ) to make Glucose and Oxygen ( O2 ).
Note : Endothermic reaction results in cooling of environment.
Exothermic reaction : Any chemical reaction that releases heat to the environment in the form of heat or light is termed as exothermic reaction. Exothermic reactions may be warm or explosive.
Example : Any combustion reaction, respiration , rusting of iron etc are some of the examples of exothermic reaction. In these cases heat is released as a result of exothermic reaction.
Note : Exothermic reaction is exactly the opposite of endothermic reaction.
