Question

Which of the following is (are) true when HCl (g) is passed through water?
(i) It does not ionise in the solution as it is a covalent compound.
(ii) It ionises in the solution.
(iii) It gives both hydrogen and hydroxyl ion in the solution.
(iv) It forms hydronium ion in the solution due to the combination of hydrogen ion with water molecule.

• A. (i) only
• B. (iii) only
• C. (ii) and (iv)
• D. (iii) and (iv)

Answer 1

The correct option is C (ii) and (iv)

HCl gas is a covalent compound but in the aqueous solution, it ionizes to form hydrogen ions and chloride ions. In the aqueous solution, hydrogen ions react with a water molecule to form hydronium ions.

$HCl\left(g\right)\leftrightarrow H^{+}+{Cl}^{-}\stackrel{Aqueousso{l}^n}{\to }{H}_3{O}^{+}+{Cl}^{-}$