question_answer

Potassium ferrocyanide is an example of

A)  tetrahedral      

B)  octahedral

C)  square planar                  

D)  linear

Correct Answer: B

Solution :

                                \[{{K}_{4}}[Fe{{(CN)}_{6}}]4{{K}^{+}}+{{[Fe{{(CN)}_{6}}]}^{4-}}\] The oxidation number of Fe in\[{{[Fe{{(CN)}_{6}}]}^{4-}}\]is +2. \[F{{e}^{2+}}-1{{s}^{2}},2{{s}^{2}}2{{p}^{6}},3{{s}^{2}}3{{p}^{6}}3{{d}^{6}},4{{s}^{0}}4p\] Since\[C{{N}^{-}}\]is a strong field ligand, pairing occurs and the hybridisation of\[{{[Fe{{(CN)}_{6}}]}^{4-}}\]is \[{{d}^{2}}s{{p}^{3}}\]and structure is octahedral.