Which of the following sets correctly represents the increasing paramagnetic property of the ion?

Options

A. `Cu^(2+)lt V^(2+)lt Cr^(2+)lt Mn^(2+)`
B. `Cu^(2+)lt Cr^(2+)lt V^(2+)lt Mn^(2+)`
C. `Mn^(2+)lt V^(2+)lt Cr^(2+)lt Cu^(2+)`
D. `Mn^(2+)lt Cu^(2+)lt Cr^(2+)lt V^(2+)`

Answer

A

Explanation

Species having unpaired electron shows paramagnetic behaviour.
`Cu^(2+)(27) to 1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)3d^(9)to1" unpaired "e^(-)`
`Cr^(2+)(22) to 1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)3d^(4)to 4" unpaired "e^(-)`
`V^(2+)(23)to1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)3d^(3)4s^(2)to 3" unpaired "e^(-)`
`Mn^(2+)(23)to 1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)4d^(0)3d^(5)to 5" unpaired "e^(-)`
Thus, correct order of increasing paramagnetic behaviour of ions is
`Cu^(2+) lt V^(2+) lt Cr^(2+) lt Mn^(2+)`.
Greater the number of unpaired electrons more is the paramagnetic behaviour.