Question

Give an example of an exothermic reaction.

Answer 1

Part 1: Exothermic reaction:

• A reaction in which heat energy is released to the surroundings is called an exothermic reaction.

Part 2: Example of exothermic reaction:

• The formation of Calcium hydroxide or slaked lime when water is added to Calcium oxide or quick lime releases heat.
• The reaction is as follows: $\underset{\mathrm{Calcium}\mathrm{oxide}}{\mathrm{CaO}\left(\mathrm{s}\right)}+\underset{\mathrm{water}}{{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}\to \underset{\mathrm{Calcium}\mathrm{hydroxide}}{\mathrm{Ca}{\left(\mathrm{OH}\right)}_2\left(\mathrm{aq}\right)}+\mathrm{heat}$