Question

In which of the following, heat energy will be evolved?

• A. Burning of L.P.G.
• B. Dissolution of $N{H}_{4}Cl$ in water
• C. Decomposition of AgBr in the presence of sunlight
• D. Electrolysis of water

Answer 1

The correct option is A Burning of L.P.G.

Burning of L.P.G. is a chemical reaction in which hydrocarbon is burnt, and it produces carbon dioxide, heat and water. While Electrolysis of water, Dissolution of ${\mathrm{NH}}_4\mathrm{Cl}$in water and Decomposition of AgBr absorbs heat. There is no release of heat during these reactions.