Which of the following has the maximum number of unpaired electrons?

Options

A. `Mg^(2+)`
B. `Ti^(3+)`
C. `V^(3+)`
D. `Fe^(2+)`

Answer

D

Explanation

The greater the number of unpaired electrons, the higher the magnetic moment.
`Mg= "…….." 3s^(2), Mg^(2+)="…….."3s^(0)`
No unpaired electron
`Ti=3d^(2)4s^(2), Ti^(3+)=3d^(1) 4s^(0)`
One unpaired electron
`V=3d^(2)4s^(2), V^(3+)=3d^(2) 4s^(0)`
Two unpaired electrons
`Fe=3d^(6) 4s^(2), Fe^(2+)=3d^(6) 4s^(0)`
Four unpaired electrons