Answer :
Exothermic reaction :The reaction in which heat is released along with the product is known as exothermic reaction. e.g. Burning of natural gas \( CH_{4}{(g)} + O_{2}{(g)}\rightarrow CO_{2}{(g)}+2H_{2}O\) Endothermic reaction:The reaction in which energy is is known as endothermic reaction. e.g.\( 2AgCl_{(s)}\rightarrow 2Ag_{(s)}+Cl_{2}{(g)}\)