Question

Explain the following with reasons: (i) Transition metals generally form coloured compounds.
(ii) Transition metals and their maximum compounds are paramagnetic.

Hint:

Colour in transition metal compounds arises from d–d transitions; paramagnetism from unpaired d-electrons.

Answer 1

(i) Coloured compounds.
Transition metals have partially filled d-orbitals. When light falls, electrons undergo d–d transitions, absorbing certain wavelengths, and the complementary colour is observed. Example: \(\text{Ti}^{3+}\) (violet), \(\text{Cu}^{2+}\) (blue).
(ii) Paramagnetism.
Transition metals and their ions often contain unpaired d-electrons. These unpaired electrons produce magnetic moments, leading to paramagnetic behaviour. Example: Fe\(^{2+}\), Mn\(^{2+}\).