(i) A rection in which heat is given away when reactants are transformed into the products is called as exothermic reaction.
(ii) e.g. formation of ice from water, dissolution of sodium hyfroxide in water.
(iii) When solid NaOH is dissolved in water, heat is given out and therefore, the temperature increases.
(iv) `{:(NaOH_((s))+H_(2)O _((l))to NaOH _((aq))+"Heat"),("Sodium" " ""Water" " ""Sodium hydroxide"),("hydroxide"):}`
