Question

Most transition metals

I : Form sets of compounds which display different oxidation states of the metal.

II : Form coloured ions in solution.

III : Burn vigorously in oxygen.

IV : Form complex compound.

of these :

• A. I, II, III are correct
• B. II, III, IV are correct
• C. I, II are correct
• D. All are correct

Answer 1

Answer: (C)

I, II are correct

Answer 2

(1) In Cr2O72–, the valence shell electron configuration of Cr(VI) is 3d0. Thus Cr(VI) is diamagnetic but coloured due to the charge transfer spectrum.

(2) In (NH4)2 [TiCl6], the valence shell electron configuration of Ti(IV) is 3d0. Thus Ti(IV) is diamagnetic and colourless.

(3) In VOSO4, the valence shell electron configuration of V(IV) is 3d1. Thus V(IV) is paramagnetic and blue coloured due to d-d transition.

(4) In K3[Cu(CN)4], the valence shell electron configuration of Cu(I) is 3d10. Thus Cu(I) is diamagnetic and colourless.