Para hydrogen is-

1. Less stable than ortho hydrogen.

2. More stable than ortho hydrogen.

3. As stable as ortho hydrogen.

4. None of the above.

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 among the following that has hydrogen in the atomic state is –

1. Metallic hydrides                           

2. Ionic hydrides

3. Molecular hydrides                       

4. Water

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

An isotope that is used as a tracer in a chemical reaction is-

1. ${\mathrm{H}}_1^1$

2. ${\mathrm{H}}_1^2$

3. ${\mathrm{H}}_1^3$

4. Ortho hydrogen

The hydride formed by an element having valence shell electronic configuration $3d^{6}4s^2$ is -

1. Saline hydride.

2. Electron rich hydride.

3. Interstitial hydride.

4. No hydride.

The freezing point of heavy water in comparison to normal water is -

1. Higher 

2. Lower 

3. Same

4. None of the above

Permutit is chemically known as:

1. Hydrated sodium aluminium silicate

2. Sodium hexa meta-phosphate

3. Sodium silicate

4. Sodium meta-aluminate

Calcium carbide with heavy water generates-

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

2.  ${\mathrm{C}}_2{\mathrm{D}}_2$

3.  ${\mathrm{D}}_2{\mathrm{O}}_2$

4.  ${\mathrm{CaD}}_2$

Match the column:-