Question

Why is the electrolysis of acidulated water considered to be an example of catalyzed reaction?

Answer 1

Electrolysis

• The decomposition of an ionic compound in a molten state or aqueous solution carried by the passage of an electric current accompanying chemical reactions is known as electrolysis.

Acidulated water

• Water that contains a few drops of dilute sulphuric acid $\left({\text{H}}_{\text{2}}{\text{SO}}_{\text{4}}\right)$ is known as acidulated water.
• For the acidification of water, dilute sulphuric acid is preferred to dilute nitric acid $\left({\text{HNO}}_3\right)$ or dilute hydrochloric acid $\left(\text{HCl}\right)$.
• This is because nitric acid or hydrochloric acid being volatile acids may decompose forming nitrate $\left({\mathrm{NO}}_3^{-}\right)$ or chloride $\left({\mathrm{Cl}}^{-}\right)$ ions which obstruct the electrolysis process.

Electrolysis of acidulated water

• Distilled water is a non-electrolyte and does not allow electricity to pass through it.
• Adding a small amount of dilute sulphuric acid leads to the ionization of water so that an electric current can be passed through the solution. This is exactly what catalysts do.
• Thus, in this process, dilute sulphuric acid acts as a catalyst.
• Therefore, the electrolysis of acidulated water can be considered to be an example of a catalyzed reaction.