Which salt undergoes hydrolysis?

1. CH₃COONa                                     

2. KNO₃

3. NaCl                                               

4. K₂SO₄

Three reactions involving ${\mathrm{H}}_2{\mathrm{PO}}_4^{-}$ are given below:

(i) H₃PO₄ + H₂O $\to$H₃O⁺ + ${\mathrm{H}}_2{\mathrm{PO}}_4^{-}$

(ii) ${\mathrm{H}}_2{\mathrm{PO}}_4^{-}$ + H₂O $\to$${\mathrm{HPO}}_4^{2-}$ + H₃O⁺

(iii) ${\mathrm{H}}_2{\mathrm{PO}}_4^{-}$ + OH^- $\to$H₃PO₄ +O^2-

In which of the above does ${\mathrm{H}}_2{\mathrm{PO}}_4^{-}$ act as an acid?

1. (i) only                                 

2. (ii) only

3. (i) and (ii)                           

4. (iii) only

The compound that does not act as Lewis acid is:

1. AlCl₃                                           

2. BF₃

3. NH₃                                             

4. FeCl₃

The conjugate base of [Al(H₂O)₃(OH)₃] is:

1. [Al(H₂O)₃(OH)₂]⁺                           

2. [Al(H₂O)₃(OH)₂O]^-

3. [Al(H₂O)₃(OH)₃]^-                           

4.  [Al(H₂O)₂(OH)₄]^-

Which is Lewis base?

1. HCl               

2. HNO₃

3. HF               

4. NH₃