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Question
Explain the types of double displacement reactions with examples.
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Solution
There are two major classes of double displacement reactions. They are,
(i) Precipitation Reactions: When aqueous solutions of two compounds are mixed, if they react to form an insoluble compound and a soluble compound, then it is called a precipitation reaction.
\[\ce{Pb(NO3)2_{(aq)} + 2KI_{(aq)}→ PbI2_{(s)}↓ + 2KNO3_{(aq)}}\]
(ii) Neutralisation Reactions: Another type of displacement reaction in which the acid reacts with the base to form a salt and water. It is called ‘neutralisation reaction’ as both acid and base neutralize each other.
\[\ce{NaOH_{(aq)} + HCl_{(aq)}-> NaCl_{(aq)} + H2O_{(l)}}\].
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