Question

Which of the following is a salt of weak acid and a strong base? *
a. NaCl. b. KNO3. c. Na2CO3. c. (NH4)2CO2​

Answer 1

Explanation:

Salt of strong acid and weak base produces acidic solution

So, NH

4

Cl⇒(NH

4

OH+

HCl

)

S.A

others are made from (S.A+S.B) ⇒ Neutral in H

2

O

Thus, only NH

4

Cl will produce acid solution.

Answer 2

Given: 4 different salts of different acidic/basic characters are given.

To find: The salt which is made of weak acid and strong base.

Explanation: Analysis of the given salts:

NaCl is made of NaOH(sodium hydroxide) and HCl(hydrochloric acid). NaOH is a strong base and HCl is a strong acid. During reaction, both neutralise each other to form a neutral NaCl.

KNO3 is made of KOH(pottasium hydroxide) and HNO3( nitric acid). KOH is a strong base and HNO3 is a strong acid. They also form neutral KNO3.

Na2CO3 is made of NaOH(sodium hydroxide) and H2CO3( carbonic acid). NaOH is a strong base and H2CO3 is a weak acid. They react to form basic Na2CO3.

(NH4)2CO3 is made of NH4OH(ammonium hydroxide) and H2CO3 (carbonic acid). NH4OH is a weak base and H2CO3 is a weak acid.

Therefore, the salt of weak acid and strong base is Na2CO3.