High spin complex of a 3d metal ion M has a magnetic moment of 2.9 B.M. in octahedral coordination environment and 4.1 B.M. in tetrahedral environment. The M ion is
(a)$\mathrm{Co^{2+}}$
(b)$\mathrm{Ni^{2+}}$
(c)$\mathrm{Cu^{2+}}$
(d)$\mathrm{Co^{2+}}$
Answer
SELF-PRACTICE — the source book printed no answer.
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