Question

What property of Sulphuric acid is shown by the reaction of concentrated Sulphuric acid when heated with

(A) Potassium nitrate

(B) Carbon.

Answer 1

(A) Non-volatile nature:

• Non-volatile nature is shown by the conc. Sulphuric acid $\left(H_2{\mathrm{SO}}_4\right)$when it is heated with Potassium nitrate $\left({\mathrm{KNO}}_3\right)$.
• When conc. Sulphuric acid is heated with Potassium nitrate, it will give Nitric acid fumes $\left({\mathrm{HNO}}_3\right)$ and Potassium bisulphate $\left({\mathrm{KHSO}}_4\right)$ as a product.
• Non-volatile Sulphuric acid produces volatile Nitric acid. c

Balanced chemical equation:-

$\underset{\mathrm{Potassium}\mathrm{nitrate}}{\underbrace{{\mathrm{KNO}}_3\left(\mathrm{s}\right)}}+\underset{\mathrm{Sulphuric}\mathrm{acid}}{\underbrace{{\mathrm{H}}_2{\mathrm{SO}}_4\left(\mathrm{l}\right)}}\to \underset{\mathrm{Potassium}\mathrm{bisulphate}}{\underbrace{{\mathrm{KHSO}}_4\left(\mathrm{l}\right)}}+\underset{\mathrm{Nitric}\mathrm{acid}}{\underbrace{{\mathrm{HNO}}_3\left(\mathrm{g}\right)}}$

(B) Oxidizing nature:

• Oxidizing nature of Sulphuric acid $\left(H_2{\mathrm{SO}}_4\right)$is shown, when it is heated with Carbon.
• Carbon is a non-metal. Non-metals form their respective oxides when heated with conc. ${\mathrm{H}}_2{\mathrm{SO}}_4$.
• During this reaction Carbon$\mathbf{\left(}\mathbf{C}\mathbf{\right)}$ is oxidized to Carbon dioxide gas $\left({\mathrm{CO}}_2\right)$.

Balanced chemical equation:-

$$\begin{gathered} \mathrm{C}\left(\mathrm{s}\right)+2{\mathrm{H}}_2{\mathrm{SO}}_4\left(\mathrm{l}\right)\to 2{\mathrm{SO}}_2\left(\mathrm{g}\right)+2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{g}\right)+{\mathrm{CO}}_2\left(\mathrm{g}\right) \\ \mathrm{Carbon}\mathrm{Sulphuric}\mathrm{Sulphur}\mathrm{water}\mathrm{Carbon} \\ \mathrm{acid}\mathrm{dioxide}\mathrm{dioxide} \\ \mathrm{gas}\mathrm{gas} \end{gathered}$$