2 Marks Questions

1.  Give an explanation for the catalytic properties shown by transition metals.

Ans. Catalytic properties shown by transition metals can be explained due to

(i)  Presence of variable valency and ability of elements to form complexes.

(ii) Surface of metals where the reaction can occur.

2.  Write some characteristics of interstitial compounds.

Ans.  Some characteristics of interstitial compounds are

(i)  They have high melting points.

(ii) They are very hard.

(iii) They retain metallic lusture.

(iv) They are chemically inert.

3. Describe the steps of preparation of?

Ans. Potassium Permanganate is prepared in two steps:

Step 1: Fusion of with KOH and oxidizing agent to give dark green.

Step 2: Disproportionation of manganate ions to give permanganate ions.

4. Give some of the uses of?

Ans. Uses of potassium permanganate –

(a) As an oxidizing agent.

(b) For bleaching of wool, cotton & silk.

(c) For decolourisation of oils.

5. What happens when

 (a) A lanthonoid reacts with dil- acid

(b) A lanthonoid reacts with water.

Ans. (i) When a Lanthanoid reacts with dil- acid, it liberate hydrogen gas.

(ii) When a Lanthanoid reacts with water, it forms hydroxide.