(a) Name the catalyst which helps in the conversion of sulphur dioxide to sulphur trioxide in step C.

(b) In the Contact process for the manufacture of sulphuric acid, sulphur trioxide is not converted to sulphuric acid by reacting it with water. Instead a two steps procedure is used. Write the equations for the two steps involved in D.

(c) What type of substance will liberate sulphur dioxide from sodium sulphite in step E?

(d) Write the equation for the reaction by which sulphur dioxide is converted to sodium sulphite in step F.

The gas evolved when dil. sulphuric acid reacts with iron sulphide.

1. Hydrogen sulphide
2. Sulphur dioxide
3. Sulphur trioxide
4. Vapour of sulphuric acid.

Dilute sulphuric acid will produce a white ppt. when added to a solution of:

1. Copper nitrate
2. Zinc nitrate
3. Lead nitrate
4. Sodium nitrate

On passing SO₂ through chlorine water, the acid produced is :

1. H₂SO₃
2. HNO₃
3. H₂SO₄
4. H₂PO₄