Question

Classify bases on the basis of their strength. [3 MARKS]

Answer 1

Each point: 1.5 Mark

(i) Strong alkalis or bases: The alkalis or bases which undergo almost complete ionisation in aqueous solution are known as strong alkalis or bases.

Example– $\text{NaOH}\text{(aq)}\to {\text{Na}}^{+}\text{(aq)}+{\text{OH}}^{-}\text{(aq)}$

(ii) Weak alkalis or bases:

The alkalis or bases which undergo only partial ionisation in aqueous solution are known as weak alkalis or bases.

Example– ${\text{Ca(OH)}}_2\text{(aq)}$ $\to$ ${\text{Ca}}^{2+}\text{(aq)}$ + ${\text{2OH}}^{-}\text{(aq)}$