In which of these options do both consituents of the pair have the same magnetic moment-

Options

A. `Zn^(2+)` and `Cu^(+)`
B. `Co^(2+)` and `Ni^(2+)`
C. `Mn^(4+)` and `Co^(2+)`
D. `Mg^(2+)` and `Sc^(+)`

Answer

A, C

Explanation

`E_(n) = (13.6z^(2))/(n^(2))`
as move away from the nucleus the energy increase, hence energy is maximum at infinite distance from the nucleus.