The pH of 0.1M soution of the folowing salts increases in the order:

1. NaCl < NH₄Cl < NaCN < HCl

2. HCl < NH₄Cl < NaCl < NaCN

3. NaCN < NH₄Cl < NaCl < HCl

4. HCl < NaCl < NaCN < NH₄Cl 

Calculate the pOH of a solution at 25$°$C that contains 1x10^-10 M of hydronium ion.        

1. 7.00                         

2. 4.00

3. 9.00                         

4. 1.00

For a given solution pH = 6.9 at 60$°$C, where K_w=10^-12. The solution is:

1. acidic                                         

2. basic

3. neutral                                         

4. unpredictable

Incorrect statement among the following is: 

1. Addition of one drop of concentrated HCl in NH₄OH solution decreases pH of the solution.

2. A solution of the mixture of one equivalent of each of CH₃COOH and NaOH has a pH of 7

3. pH of pure neutral water is not zero.

4. A cold and concentrated H₂SO₄ has lower H⁺ ion concentration than a dilute solution of H₂SO₄ 

What happens to pH of a solution when NH₄Cl crystal is added to a dilute solution of NH₄OH?

1. Decreases                                   

2. Increases

3. Remains unaffected                       

4. All of the above

The phenomenon of interaction of anions and cations furnished by an electrolyte with the H⁺ and  OH^- ions of water to produce acidic nature or alkalinity is known as hydrolysis. In hydrolysis:

1. the pH may either increase or decrease

2. all the salts (except those made up with strong acid and base) undergo hydrolysis

3. the variation of pH depends upon the nature of salts as well as on the temperature

4. all of the above

Which of the following statements is not true?

1. The pH of 10^-8 N HCl is 8.

2. 96500 coulomb of electricity is passed through a CuSO₄ solution deposit 1g of equivalent of Cu at cathode.

3. The conjugate base of H₂P${\mathrm{O}}_4^{-}$ is HP${\mathrm{O}}_4^{2-}$.

4. pH + pOH = 14 for all aqueous solution.

Which of the following salts will give the highest pH in the water?                   

1. KCl           

2. NaCl         

3. Na₂CO₃     

4. CuSO₄

An aqueous solution of which salt has the lowest pH?

1. NaOH                 

2. NH₄Cl

3. Na₂CO₃             

4. NaCl

The pH of 0.1 M solution of anilium chloride is (K_a of ${\mathrm{C}}_6{\mathrm{H}}_5{\mathrm{NH}}_3^{+}$ = 10^-6)

(1) 3.5

(2) 3

(3) 4.5

(4) none of these