Question

The process that is not endothermic in nature is :

• A. $\mathrm{H}\left(\mathrm{g}\right)+{\mathrm{e}}^{–}\to {\mathrm{H}}^{-}\left(\mathrm{g}\right)$
• B. $\mathrm{Na}\left(\mathrm{g}\right)\to {\mathrm{Na}}^{-}\left(\mathrm{g}\right)\to {\mathrm{e}}^{–}$
• C. $\mathrm{Ar}\left(\mathrm{g}\right)+{\mathrm{e}}^{–}\to {\mathrm{Ar}}^{-}\left(\mathrm{g}\right)$
• D. ${\mathrm{O}}^{–}\left(\mathrm{g}\right)+{\mathrm{e}}^{–}\to {\mathrm{O}}^{2-}\left(\mathrm{g}\right)$

Answer 1

The correct option is A

$\mathrm{H}\left(\mathrm{g}\right)+{\mathrm{e}}^{–}\to {\mathrm{H}}^{-}\left(\mathrm{g}\right)$

The explanation for the correct option:

A: $\mathrm{H}\left(\mathrm{g}\right)+{\mathrm{e}}^{–}\to {\mathrm{H}}^{-}\left(\mathrm{g}\right)$

Endothermic Reaction:

• Chemical processes referred to as endothermic reactions occur when the reactants take in heat energy from their environment to create products.
• These reactions produce a cooling effect by bringing the temperature of the space around them down.
• Ice cubes absorb heat energy from their surroundings and melt to generate liquid water as an example of an endothermic physical process (no chemical bonds are broken or formed).

Given Reaction:

• $\mathrm{H}\left(\mathrm{g}\right)+{\mathrm{e}}^{–}\to {\mathrm{H}}^{-}\left(\mathrm{g}\right)$
• In the above reaction energy is released i.e. this reaction is exothermic reaction.

Final Answer: Therefore, Option A is the correct option.