The ionic conductance of the following cations in a given concentration is in the order

Options

A. `Li^(+)ltNa^(+)ltK^(+)ltRb^(+)`
B. `Li^(+)gtNa^(+)gtK^(+)gtRb^(+)`
C. `Li^(+)ltNa^(+)gtK^(+)gtRb^(+)`
D. `Li^(+)=Na^(+)ltK^(+)ltRb^(+)`

Answer

A

Explanation

Due to extensive hydration of smaller alkali metal cations, the ionic radii is in the order
`Li^(+)gtNa^(+)gtK^(+)gtRb^(+)`
As such mobility in water is in the order
`Li^(+)ltNa^(+)ltK^(+)ltRb^(+)`