Question

In order to study saponification reaction, we first prepare 20% solution of sodium hydroxide. If we record the temperature of this solution just after adding sodium hydroxide flakes to water and also test its nature using litmus, it may be concluded that the process of making this solution is

(A) exothermic and the solution is alkaline

(B) endothermic and the solution is alkaline

(C) endothermic and the solution is acidic

(D) exothermic and the solution is acidic

Answer 1

Dissolution of sodium hydroxide in water evolves large amount of heat. Thus, it is an exothermic reaction. Since sodium hydroxide is a base, its solution in water will be alkaline when tested with litmus paper (red litmus turns blue).

Hence, the correct option is A.