Question

Question 29.
Show the dilute aqueous solution of hydrochloric acid
(a) ${\text{H}}_3{\text{O}}^{+}+{\text{Cl}}^{-}$
(b) ${\text{H}}_3{\text{O}}^{+}+{\text{OH}}^{-}$
(c) ${\text{Cl}}^{-}+{\text{OH}}^{-}$
(d) unionised HCl

Answer 1

When HCl is passed through water then being a polar covalent compound it ionises as:

$\text{HCl (aq)}\to {\text{H}}^{+}+{\text{Cl}}^{-}$

It forms hydronium ion in the solution due to the combination of hydrogen ion with water molecule. The reaction takes place as follows:

${\text{H}}^{+}+{\text{H}}_2\text{O}\to {\text{H}}_3{\text{O}}^{+}$

So, dilution of HCl will form hydronium ion and chloride ion. Hence, option (a) is correct.