Question

Correct order of paramagnetism of tripositive cation of Cr, Mn, Fe, Co is :
A. `Crlt Mn lt Felt Co`
B. `Crlt Mn = Felt Co`
C. `Cr = Fe lt Mn lt Co`
D. `Cr lt Mn = Co lt Fe`

Answer 1

Correct Answer - D
No. of unpaired electron
`{:(Cr^(+3),=,[Ar]4s3d3d^(3),rarr,3,),(Mn^(+3),=,[Ar]3d^(4)4s^(0),rarr,4,),(Fe^(+3),=,[Ar]3d^(5)4s^(0),rarr,5,),(Co^(+3),=,[Ar]3d^(6)4s^(0),rarr,4,):}`
`Cr^(+3) lt Mn^(+3) -= Co^(+3) lt Fe^(+3)`
`Cr lt Mn = Co lt Fe`