Hydrolysis of salts — NEET & JEE Questions

Question 1 · difficulty L1 · recall

A salt formed from a strong acid and a strong base generally gives an aqueous solution that is approximately

• A. neutral
• B. strongly acidic
• C. strongly basic
• D. always buffered

Question 2 · difficulty L2 · understanding

A salt of a weak acid and a strong base, such as sodium acetate, generally gives a solution that is

• A. acidic
• B. basic
• C. neutral
• D. always pH 7 regardless of concentration

Question 3 · difficulty L2 · understanding

A salt of a strong acid and a weak base, such as ammonium chloride, generally gives a solution that is

• A. basic
• B. acidic
• C. neutral
• D. strongly alkaline

Question 4 · difficulty L2 · understanding

For the acetate ion in water, the hydrolysis equilibrium can be represented as

• A. $CH_3COO^-+H_2O\rightleftharpoons CH_3COOH+OH^-$
• B. $CH_3COO^-+H_2O\rightleftharpoons CH_3CO^++2OH^-$
• C. $CH_3COO^-+H^+\rightarrow CH_4+CO_2$
• D. $CH_3COO^-\rightarrow Na^++Cl^-$

Question 5 · difficulty L3 · understanding

Given below are two statements : Statement (I) : Aqueous solution of ammonium carbonate is basic. Statement (II) : Acidic/basic nature of salt solution of a salt of weak acid and weak base depends on $$K_a$$ and $$K_b$$ value of acid and the base forming it. In the light of the above statements, choose the most appropriate answer from the options given below :

• A. Both Statement I and Statement II are correct
• B. Statement I is correct but Statement II is incorrect
• C. Both Statement I and Statement II are incorrect
• D. Statement I is incorrect but Statement II is correct

Question 6 · difficulty L3 · understanding

$$20 \mathrm{~mL}$$ of $$0.1\, \mathrm{M} \,\mathrm{NH}_{4} \mathrm{OH}$$ is mixed with $$40 \mathrm{~mL}$$ of $$0.05 \mathrm{M} \mathrm{HCl}$$. The $$\mathrm{pH}$$ of the mixture is nearest to : (Given : $$\mathrm{K}_{\mathrm{b}}\left(\mathrm{NH}_{4} \mathrm{OH}\right)=1 \times 10^{-5}, \log 2=0.30, \log 3=0.48, \log 5=0.69, \log 7=0.84, \log 11= 1.04)$$

• A. 3.2
• B. 4.2
• C. 5.2
• D. 6.2

Question 7 · difficulty L3 · understanding

Given below are two statements : One is labelled as Assertion A and the other labelled as reason R Assertion A : During the boiling of water having temporary hardness, Mg(HCO 3 ) 2 is converted to MgCO 3 . Reason R : The solubility product of Mg(OH) 2 is greater than that of MgCO 3 . In the light of the above statements, choose the most appropriate answer from the options given below :

• A. Both A and R are true but R is not the correct explanation of A
• B. A is true but R is false
• C. Both A and R are true and R is the correct explanation of A
• D. A is false but R is true

Question 8 · difficulty L3 · understanding

The percentage dissociation of a salt $\left(\mathrm{MX}_3\right)$ solution at given temperature (van't Hoff factor $\mathrm{i}=2$ ) is ___________ %(Nearest integer)

Question 9 · difficulty L3 · understanding

The observed and normal molar masses of compound $\mathrm{MX}_2$ are 65.6 and 164 respectively. The percent degree of ionisation of $\mathrm{MX}_2$ is __________%. (Nearest integer)

Question 10 · difficulty L3 · understanding

The dissociation constant of a substituted benzoic acid at 25$$^\circ$$C is 1.0 $$\times$$ 10$$^{-4}$$. The pH of a 0.01 M solution of its sodium salt is __________.