Why a solution of `[Ni(CN)_4]^(2-)` is colourless?

A solution of [Ni(H_(2)O)_(6)]^(2+) is green but a solution of [Ni(CN)_(4)]^(2-) is colourless Explain.

STATEMENT -1 A solution of [Ni(H_(2)O)_(6)]^(2+) is geen but a solution of [Ni(CN)_(4)]^(2-) is colourless. STATEMENT-2 : : Energy difference between d level ( i.e.Delta )for H_(2)O complex (paramagnetic) is in the visible region and that for the cyano complex (diamagnetic)is in the UV region.

Assertion A solution of [Ni(H_(2)O)_(6)]^(2+) is green but a solution of [Ni(CN)_(4)]^(2+) is colourless Reason [Ni(CN)_(4)]^(2+) is square planar complex .

(i) What type of isomerism is shown by the complex [Co(NH_(3))_(6)] [Cr(CN)_(6))] ? (ii) Why a solution of [Ni(H_(2)O)_(6)^(2+) is given while a solution of [No(CN)_(4)]^(2-) colourless ? (At. No. of Ni = 28) (iii) Write the IUPAC name of the following complex : [Co(NH_(3))_(5) (CO_(3))] Cl

Why solution of \([Ni(H_{2}O)_{6})]^{2+}\) is green while solution of \([Ni(H_{2}O)_{4})]^{-}\) is colourless. [at no of Ni=28]