The coordination number of `Ni^(2+)` is 4.
`NiCl_(2) + KCN ("excess") rarr A ("cyano comples")`
`NiCl_(2) + conc. HCl ("excess") rarr B ("chloro complex")`
The hybridisation of A and B are

Options

A. Potassium tetracyanonickeltate(II), potassium tetrachloronickeltate(II)
B. Tetracyanopotassium nickelate(II), tetrachloro-potassiumnickelate(II)
C. Tetracyanonickel(II), tetrachloronickel(II)
D. Potassium tetracyanonickel(II), potassium tetrachloronickel(II)

Answer

A

Explanation

`NiCl_(2)+4 KCNrarrK_(2)underset("tetracyanonickelate(II)")underset("Potassium")underset(("A"))([Ni(CN)_(4)])+2KCl`
`K_(2)[Ni(CN)_(4)]+4HCl ("excess")rarr underset("tetrachloronickelate(II)")underset("Potassium")(K_(2)[NiCl_(4)])+HCN`