A solution of `[Ni(H_2O)_6]^(2+)` is green but a solution of `[Ni(CN)_4]^(2-) is colourless.Explain.

Answer the following: Aqueous solution of Ti^(4+) is colourless, but aqueous solution of Ti^(3+) is violet in colour. Explain.

[Ti (H_2O)_6]^(3+) is coloured while [Sc(H_2O)_6]^(3+) is colourless. Explain.

Explain why [Ti (H_2O)_6]^(3+) is violet while [Ti (H_2O)_6]^(4+) is colourless.

[Cr(NH_3)_6]^(3+) is paramagnetic while [Ni(CN)_4]^(2-) is diamagnetic. Explain why?

Find the oxidation number of Ni [Ni(CN)_3 Cl]^(2-)

[Fe(H_2O)_6]^(3+) is strongly paramagnetic whereas [Fe(CN)_6]^(3-) is weakly paramagnetic. Explain.

Explain [Fe(H_2O)_6]^(3+) is paramagnetic.

Explain: [Ni (CN)_4]^(2-) is diamagnetic while [Ni(Cl)_4]^(2-) is paramagnetic.