question_answer

According to MOT which of the following is correct for potassium hexa cyano ferrate (III)?

A)  It is a octahedral complex

B)  \[{{t}_{2g}}\] Orbital contains the \[{{e}^{-}}\] of metal

C)  For iron, overlapping between empty orbitals and ligand orbitals takes place

D)  All of the above

Correct Answer: D

Solution :

For the complex \[{{[Fe{{(CN)}_{6}}]}^{4-}}\] Oxidation state of \[Fe=+II\] Coordination number = 6 Electronic configuration of \[F{{e}^{2+}}\]\[F{{e}^{2+}}=1{{s}^{2}},2{{s}^{2}},3{{s}^{2}},3{{p}^{6}},3{{d}^{6}},4{{s}^{0}},4{{p}^{0}}\] Since, \[-CN\] is ligand of strong field. Hence, it paired up electrons of d-orbital. So, Hybridization \[={{d}^{2}}s{{p}^{3}}\] Magnetic moment = zero Number of unpaired electrons = zero Geometry = octahedral.