Question

During the manufacture of sulphuric acid, a chemist collected the gas formed after catalytic oxidation of sulphur dioxide.

1. Name the gas collected.
2. Which acid is formed when the gas collected by the chemist is dissolved directly in water?
3. Why should we not dissolve this gas directly in water?

Answer 1

(a) The gas formed after catalytic oxidation of sulphur dioxide is sulphur trioxide (SO₃).

(b) When (SO₃) is dissolved in water, it forms sulphuric acid (H₂SO₄).

(c) It is not dissolved directly in water because the reaction is highly exothermic, resulting in the formation of a dense mist of acid droplets that is extremely difficult to condense.