Question

State the conditions required for the following reactions to take place:

The conversion of sulphur dioxide to sulphur trioxide.

State the conditions required for the conversion of sulphur dioxide to sulphur trioxide to take place.

Answer 1

1. The reaction is exothermic, so it is carried out at a moderately low temperature of about 450°C.
2. High pressure favours the reaction because the products occupy less volume than the reactants.
3. Use air containing an excess of oxygen.
4. A suitable catalyst such as vanadium(V) oxide (V₂O₅) or platinum is required.
5. The gases should be pure and dry.
   \[\ce{2SO2 + O2 ⇌[V2SO5][450°C]2SO3}\]