Endothermic Reaction

All chemical reactions use energy to break bonds and release energy when new bonds form. Endothermic reactions are reactions that absorb heat from their surroundings.

So, how does it work? The term "endothermic" literally means "taking in heat." In these reactions, breaking bonds in the reactants requires more energy than is released when new bonds form in the products.

As a result, heat is taken from the surroundings, causing a cooling effect, sometimes enough to freeze liquids.

Take the ice pack, for example. Inside it, water and a chemical like ammonium nitrate are kept separate. When you squeeze the pack, they mix, and the reaction absorbs heat from the surrounding water, making the pack feel cold.

Even physical changes, like the melting of ice, cause a cooling effect, as the ice absorbs heat from your hand to melt.

Plants also rely on endothermic reactions during photosynthesis, where sunlight provides the energy to transform carbon dioxide and water into glucose and oxygen.