Calculate the magnetic moment of a divalent ion in aqueous solution if its atomic number is 25.

Options

A. `3.0 BM`
B. `4.9 BM`
C. `5.9BM`
D. `6.9 BM`

Answer

C

Explanation

Atomic number `25` corresponds to the first transition series. For these elements, the magnetic moment associted with unpaired electron is given as
`mu = sqrt(n(n +1))`
where `n` is the number of unpaired electrons.
`(Z = 25)rArr 1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)3d^(5)4s^(2)`. After the removal of `2e^(-)s`, it become `[Ar] 3d^(5)`having unpiared eletrons. thus,
`mu = sqrt(5(5+2))BM = 5.9 BM`