question_answer

Which of the following option is having maximum number of unpaired electrons

A)  A tetrahedral d6 ion

B)  \[{{[Co{{({{H}_{2}}O)}_{6}}]}^{3+}}\]

C)  A square planar d7 ion

D)  A co-ordination compound with magnetic moment of 5.92 B.M.

Correct Answer: D

Solution :

[a] For tetrahedral \[{{d}^{6}}\]ion, 4 unpaired electrons [b] For \[{{[Co{{({{H}_{2}}O)}_{6}}]}^{3+}},\]0 unpaired electrons [c] For square planar \[{{d}^{7}}\] ion, 1 unpaired electrons [d] \[B.M.=\sqrt{n(n+2)},=\]unpaired electrons \[5.92\,B.M.=\sqrt{n(n+2)}\] n = 5 unpaired electrons.