Question

An aqueous solution of salt Is alkaline. It shows that the salt is made from
A) a strong acid and strong base
B) strong acid and weak base
C) a weak acid and weak base
D) A weak acid and strong base

Answer 1

Hint: A salt is a chemical compound consisting of an ionic assembly of cations and anions. Salts are composed of related numbers of cations (positively charged ions) and anions (negatively charged ions) so that the product is electrically neutral (without a net charge)

Complete Step by step answer: Types of salts
A) normal salt or neutral salt. A salt of strong acid and strong base is neutral or normal salt as both the cation and anion of the salt are weak and do not hydrolyse completely. . They are formed when acids and bases neutralize, and these salts don’t have replaceable hydrogen or hydroxyl in their formula.
Eg. $NaCl,\,N{a_2}S{O_4}$
B) Acidic salt: an acidic salt is the salt formed from strong acid and weak base. It is acidic due to cationic hydrolysis. The conjugate acid of a weak base is strong. Hence it undergoes cationic hydrolysis and forms an acidic salt.
Eg. ${(N{H_4})_2}S{O_4}$
C) Weak acid and weak base salt is neutral as both cation and anion undergo hydrolysis.
Eg. ${(N{H_4})_2}C{O_3}$
A Salt formed by the reaction of a strong base and weak acid is having an alkaline nature when dissolved in water.

Hence, option D is correct.

Note: Most of the students make mistakes and only consider the salt of strong acid and strong base as neutral, but salt of weak acid and weak base also provides neutral salt. A basic salt is the salt formed from weak acid and strong base. It is basic due to anionic hydrolysis. The conjugate base of a weak acid is strong. Hence it undergoes anionic hydrolysis and forms an acidic salt.