Sulfuric acid is manufactured by the Contact process, in which a mixture of sulfur dioxide and excess air, preheated to 450°C, is passed over a catalyst.

a. How is the sulfur dioxide made? Give an equation for the reaction.

b. Write the balanced chemical equation for the reaction that takes place between sulfur dioxide and air.

c. Name a suitable catalyst for the reaction.

d. Why is a catalyst necessary for this process?

e. The product of this reaction will react directly with water. When it does so, it forms sulfuric acid. However, the method is impractical because the reaction is exothermic and an acid mist forms. Describe the modern indirect method of changing the product of the reaction between sulfur dioxide and air to form sulfuric acid.

f. Give two uses of concentrated sulfuric acid.