How many unpaired electrons are present in `Ni^(2+)` cation? (At. No. = 28)

Options

A. 0
B. 2
C. 4
D. 6

Answer

B

Explanation

Z = 28`" For nickel"`
`therefore" "Ni=1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)4s^(2)3d^(8)," "Ni^(2+)-=1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)4s^(0)3d^(8)`
`" 2 unpaired "e^(-s)`