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

Options

A. `Rb^(+)ltK^(+)ltNa^(+) ltLi^(+)`
B. `K^(+)ltNa^(+)ltRb^(+) ltLi^(+)`
C. `Na^(+) lt Li^(+)lt K^(+)lt Rb^(+)`
D. `Li^(+) lt K^(+) lt Na^(+) lt Rb^(+)`

Answer

C

Explanation

Ease of adsorption of the hydrated alkali metal ions on an ion exchange resins decreases as the size of the alkali metal ions increases.
Since, the order of size of alkali metal ions
`Li^(+) lt Na^(+) lt K^(+) lt Rb^(+)`
the ease of adsorption follows the order
`Rb^(+) lt K^(+) lt Na ^(+) lt Li^(+)`