The compound (s) formed upon combustion of sodium metal in excess air is (are)

1. ${\mathrm{Na}}_2{\mathrm{O}}_2$

2. ${\mathrm{Na}}_3\mathrm{N}$

3. ${\mathrm{NaO}}_2$

4. NaOH

The suspension of slaked lime in water is known as

1. Lime water

2. Quick lime

3. Milk of lime

4. Washing of lime

In context with beryllium, which one of the following statements is incorrect?

1.  It is rendered passive by nitric acid

2.  It forms ${\mathrm{Be}}_2\mathrm{C}$

3. Its salts rarely hydrolyse

4.  Its hydride is electron-deficient and polymeric

Which of the following oxides is most acidic in nature?

1. MgO

2. BeO

3. BaO

3. CaO

On heating which of the following releases CO₂ most easily?

1. ${\mathrm{K}}_2{\mathrm{CO}}_3$

2. ${\mathrm{Na}}_2{\mathrm{CO}}_3$

3. ${\mathrm{MgCO}}_3$

4. ${\mathrm{CaCO}}_3$

Which one of the alkali metals forms only, the normal oxide, M₂O on heating in air?

1. Rb

2. K

3. Li

4. Na

The ease of adsorption of the hydrated alkali metal ions on ion-exchange resins follows the order

1. ${\mathrm{Li}}^{+}<{\mathrm{K}}^{+}<{\mathrm{Na}}^{+}<{\mathrm{Rb}}^{+}$

2. ${\mathrm{Rb}}^{+}<{\mathrm{K}}^{+}<{\mathrm{Na}}^{+}<{\mathrm{Li}}^{+}$

3. ${\mathrm{K}}^{+}<{\mathrm{Na}}^{+}<{\mathrm{Rb}}^{+}<{\mathrm{Li}}^{+}$

4. ${\mathrm{Na}}^{+}<{\mathrm{Li}}^{+}<{\mathrm{K}}^{+}<{\mathrm{Rb}}^{+}$