When zeolites (hydrated sodium aluminum silicate) is treated with hard water, the sodium ions are exchanged with:

1. H⁺ ion

2. Ca²⁺ ion

3. ${\mathrm{SO}}_4^{2-}$ ion

4. OH^- ion

 Hardness of water cannot be removed by -

1. Clark's method

2. Adding washing soda

3. Calgon process

4. Filtration

The method used to remove the temporary hardness of water is-

1. Synthetic resins method

2. Calgon's method

3. Clark's method

4. Ion-exchange method

Permutit is chemically known as:

1. Hydrated sodium aluminium silicate

2. Sodium hexa meta-phosphate

3. Sodium silicate

4. Sodium meta-aluminate

Exhausted permutit does not contain  –

1. ${\mathrm{Na}}^{+}$ ion                                     

2. ${\mathrm{Mg}}^{2+}$ ion

3. ${\mathrm{Al}}^{3+}$ ion                                  

4. ${\mathrm{Si}}^{4+}$ ion

A compound that can remove both temporary and permanent hardness of water is -

1. ${\mathrm{NaHCO}}_3$

2. Boiling

3. $\mathrm{Ca}{\left(\mathrm{OH}\right)}_2$

4. ${\mathrm{Na}}_6{\mathrm{P}}_6{\mathrm{O}}_{18}$

Match the column:-

A water softening reagent among the following is -

1. ${\mathrm{Ca}}_3{\left({\mathrm{PO}}_4\right)}_2$

2. ${\mathrm{Na}}_3{\mathrm{PO}}_4$

3. ${\mathrm{Na}}_6{\mathrm{P}}_6{\mathrm{O}}_{18}$

4. ${\mathrm{Na}}_2{\mathrm{HPO}}_4$

Match the items in Column I with the relevant items in Column II.

Codes

Match list-I with list-II:

Choose the correct answer from the options given below: