Question

Which of the following is an exothermic reaction?

(A) Conversion of limestone to quick lime.
(B) Conversion of silver bromide to silver and bromine gas in presence of sunlight.
(C) Formation of compost from vegetable matter.
(D) Electrolysis of water.

Answer 1

(C) Formation of compost from vegetable matter.

Reactions given in option (A), (B) and (D) are examples of endothermic reactions and require energy in form of heat, light and electricity respectively. However, decomposition of vegetable matter into compost is an example of exothermic reaction.