Question

A salt derived from strong acid and weak base will dissolve in water to give a solution which is:
A. acidic
B. basic
C. neutral
D. None of these

Answer 1

Hint: We know that salt is formed when an acid reacts with a base. This reaction is termed a neutralization reaction. This reaction is called a neutralization reaction because it involves the combination between hydrogen ions of the acid and hydroxide ions of the base to form water.

Complete step by step answer:
There are four ways by which neutralisation reactions take place. They are as follows:
1) A strong acid reacts with a strong base
2) A strong acid reacts with a weak base
3)A weak acid reacts with a strong base
4)A weak acid reacts with a weak base
Now, come to the question. We have to find out the nature of salt solution formed when a strong acid undergoes reaction with a weak base.
A strong acid reacts with a weak base in aqueous solution to form acidic solution because of the presence of free hydrogen $\left( {{{\rm{H}}^{\rm{ + }}}} \right)$ ions. This is an account of the reason that the base is not completely ionized. Let’s understand with the help of an example. HCl is a strong acid and ammonium hydroxide $\left( {{\rm{N}}{{\rm{H}}_{\rm{4}}}{\rm{OH}}} \right)$ is a weak base.
${{\rm{H}}^ + }\left( {aq} \right) + {\rm{C}}{{\rm{l}}^ - }\left( {aq} \right) + {\rm{N}}{{\rm{H}}_{\rm{4}}}{\rm{OH}}\left( {aq} \right) \to {\rm{N}}{{\rm{H}}_{\rm{4}}}^ + \left( {aq} \right) + {\rm{C}}{{\rm{l}}^ - }\left( {aq} \right) + {{\rm{H}}_{\rm{2}}}{\rm{O}}\left( l \right)$
Therefore, the type of solution formed is acidic in nature.
Hence, the correct choice is option A.

Note: Always remember that,
1) A solution of strong acid and strong base is neutral
2) A solution of strong acid and weak base is acidic
3) A solution of weak acid and strong base is basic
4)A solution of weak acid and weak base may be acidic, basic or neutral depending upon their relative strengths.