QQuestion
X – HCl ⇋ H1+ + Cl– (in solution state)
Y – PbBr2 ⇋ Pb2+ + 2Br1- (in molten state)
From the above reactions X or Y, identify the reaction which exhibits:
(a) electrolytic dissociation
(b) ionization
✓Answer
(a) Y is electrolytic dissociation.
Reason — PbBr2 is an electrovalent compound and its contains lead [Pb2+] and bromide [Br1-] ions that are held together by an electrostatic force of attraction. Melting causes the separation of these ions. Hence, it exhibits electrolytic dissociation.
(b) X is ionization.
Reason — HCl is a polar covalent compound. In gaseous state or pure liquid state, it does not conduct an electric current. When HCl is added to water, formation of Hydronium [(H3O)+] and Chloride [Cl–] ions takes place. Hence, it exhibits ionization.
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