Question

Explain why: 

(i) Transition elements form alloys.

(ii) Zn²⁺ salts are white whereas Cu²⁺ salts are coloured. 

(iii) Transition metals and their compounds act as a catalyst.

Answer 1

(i) This is because transition metals have similar atomic radii and form substitutional alloys.

(ii) Zn²⁺(3d¹⁰) salts have no impaired electrons but Cu^2- (3d⁹) salts have one unpaired electrons. Hence Zn²⁺ salts are white while Cu^2- salts are coloured.

(iii) This is because of transition metals

• have a number of unpaired electrons in their (n-1) d-orbitals

• can show variable oxidation states.

• form intermediates and provide a new reaction path having lower energy of activation.

• they can adsorb one of the reactants on their surfaces.