Question

Basic salts are formed by the neutralization of:
(A) strong acid and strong base
(B) strong acid and weak base
(C) weak acid and weak base
(D) strong base and weak acid

Answer 1

Hint: We have studied that salts are formed from neutralization reactions of acids and bases. Here the question states basic salts. Think about what a basic salt is and what the probability of formation of a basic salt using each of the given options is. Try writing some acid-base reactions and then choose the correct answer.


Complete step by step solution:
- Acids and bases react with each other to form salt and water. This reaction is known as neutralization reactions.
- There are four types of neutralization reactions.
- Strong acid-strong base neutralization reaction in which a strong acid reacts with a strong base to form a neutral salt and water. HCl reacts with NaOH to form sodium chloride and water is an example of this type of reaction.
- Strong acid-weak base neutralization reaction in which a strong acid reacts with a weak base to form an acidic salt and water. HCl reacts with ammonium hydroxide to form ammonium chloride and water is an example of this type of reaction. The ammonium ion form has the tendency to deprotonate itself and make the medium acidic. Therefore, acidic salts are formed in this reaction.
- Weak acid-weak base neutralization reaction in which a weak acid reacts with a weak base to form a neutral salt and water. Acetic acid reacts with ammonium hydroxide to form ammonium acetate and water is an example of this type of reaction. Weak acids and weak bases do not dissociate completely so, here the equilibrium is more towards the left hand side.
- Weak acid-strong base neutralization reaction in which a weak acid reacts with a strong base to form a basic salt and water. Acetic acid reacts with NaOH to form sodium acetate and water is an example of this type of reaction. The acetate ion formed has the tendency to attract protons from water which sets hydroxyl ions free. Therefore, basic salts are formed in this reaction.

- Therefore, basic salts are formed by the neutralization of weak acid and strong base.


Note: Remember acidic salts are formed when strong acid reacts with weak base. Basic salts are formed when a strong base reacts with weak acid. A weak acid or base doesn’t dissociate completely and therefore, in weak acid- weak base reactions, equilibrium is towards the left.