Which among the following is/are an exothermic reaction?
Respiration
Burning of coal
The chemical reaction in which heat is released along with the formation of products is called an exothermic reaction.
Respiration is responsible for breaking down food molecules and releasing energy, hence it is an exothermic reaction.
When we burn coal, heat energy is released, so it is an exothermic reaction.
Photosynthesis an endothermic reaction because plants absorb energy from sunlight to turn carbon dioxide and water into oxygen and glucose.
Decomposition of calcium carbonate into carbon dioxide and calcium oxide requires heat, so it is an endothermic reaction.