Match the column:-

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

Codes

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

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

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

The temporary and permanent hardness of water is caused by -
1. Permanent hardness is caused by hydrogen carbonates and temporary hardness is caused by chlorides.
2. Temporary hardness is caused by dihydrogen and permanent hardness is caused by oxides.
3. Temporary hardness is caused by insoluble hydrogen carbonates and permanent hardness is caused by chlorides.
4. Temporary hardness is caused by hydrogen carbonates and permanent hardness is caused by chlorides.