Question

Hydrogen chloride and ethanol are covalent compounds soluble in water. The aqueous solution of which of the two will conduct electric current? Write down the relevant chemical equation.

Answer 1

The compounds which dissociates into ions in aqueous solution are able to conduct electric current.

(1) Hydrogen chloride $\left(\mathrm{HCl}\right)$ and ethanol $\left({\mathrm{CH}}_3{\mathrm{CH}}_2\mathrm{OH}\right)$ both are covalent compounds soluble in water.

(2) HCl is a polar covalent compound which dissolved in water and dissociates into ions $({\mathrm{H}}_3{\mathrm{O}}^{+},{\mathrm{Cl}}^{-})$ in aqueous solution easily and gives charged particles free to move.

(3) Ethanol is a covalent compound and a non-electrolyte which do not contains dissolved ions in aqueous solution. These separate molecules of ethanol are not charged.

Hence, Hydrogen chloride (HCl) conduct electric current in aqueous solution.

Chemical equation :

$$\begin{gathered} \mathrm{HCl}+{\mathrm{H}}_2\mathrm{O}\rightleftharpoons {\mathrm{H}}_3{\mathrm{O}}^{+}\left(\mathrm{aq}\right)+{\mathrm{Cl}}^{-}\left(\mathrm{aq}\right) \\ (\mathrm{hydrogen}(\mathrm{water})(\mathrm{hydronium}\left(\mathrm{chloride} \\ \mathrm{chloride}\right)\mathrm{ion})\mathrm{ion}) \end{gathered}$$