Assign reasons for each of the following :
(i) Transiti9n metals generally form coloured compounds.
(ii) Manganese exhibits the highest oxidation state of+ 7 among the 3d series of transition elements.

Explanation

(i) Transition metals generally form coloured compounds. Because the energy of excitation of an electron ind-orbital corresponds to the visible region.
(ii) Manganese exhibits the highest oxidation state of + 7 among the 3d series of transition, elements because all the oxidation states from + 2 to+ 7. Electronic configuration of `M_n`.
`[Ar]3d^5S^2M_n^(2+):1S^2,2S^2,2P^6 3P^6 3d^5`.
It shows largest no, of oxidation states as it have maximum no. of unpaired electrons.