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

Options

A. `Li^(+) lt Na^(+) lt K^(+) lt Rb^(+)`
B. `Rb^(+) lt K^(+) lt Na^(+) lt Li^(+)`
C. `K^(+) lt Na^(+) lt Rb^(+) lt Li^(+)`
D. `Na^(+) lt Li^(+) lt K^(+) lt Rb^(+)`

Answer

B

Explanation

Larger the size of the hydrated cation , smaller is the ease of absorption . Thus , case of absorption increases in the order : `Li^(+) lt Na^(+) lt K^(+) lt Rb^(+) ` i.e., option (a) is correct .