Question

Predict the nature of the following changes whether exothermic or endothermic.

Dilution of sulphuric acid.

Answer 1

Dilution of Sulphuric acid:

1. Sulphuric acid $\left({\mathrm{H}}_2{\mathrm{SO}}_4\right)$ is one of the most concentrated acids.
2. When it is diluted with water, the reaction occurs very quickly thereby water is protonated releasing more energy in the form of heat.
3. ${\mathrm{H}}_2{\mathrm{SO}}_4\left(\mathrm{aq}\right)+{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)\to 2{\mathrm{H}}_3{\mathrm{O}}^{+}\left(\mathrm{aq}\right)+{\mathrm{SO}}_4^{2-}\left(\mathrm{aq}\right)+\mathrm{heat}$

Hence, the dilution of Sulphuric acid is an exothermic reaction.