Answer :
(a) Ni has the atomic no 28. And it has d8 configuration. As, CO is weak ligand, it is unable to cause internal pairing has make bonds with next 4 available orbital that is 1 5s and 3 4p orbital. And have sp3 hybridization and tetrahedral shade. Whereas CN is a strong field ligand and hence cause pairing and use the left vacant d orbital and take next 1 5s and 2 4p orbital. And hence has dsp2 hybridization and square planer shape.
(b) As it is an anionic complex, and have 4 cyano group, the name will be Potassium Tetracyanonickelate(II).
(c) As CN is a strong field ligand, it has the ability to cause internal pairing and use inner d orbital. So it will make inner orbital compound and the hybridization of [Fe (CN)6]3- will be d2sp3. And the shape will be octahedral.
Rate this question :


<span lang="EN-US
Chemistry - Exemplar<span lang="EN-US
Chemistry - Exemplar<span lang="EN-US
Chemistry - Exemplar<span lang="EN-US
Chemistry - Exemplar<span lang="EN-US
Chemistry - Exemplar