Sulfur trioxide is formed from sulfur dioxide in a reversible reaction. $2\text{SO}_2\text{(g)} + \text{O}_2\text{(g)} \rightleftharpoons 2\text{SO}_3\text{(g)}$ The forward reaction gives out heat. Which changes would lead to a higher equilibrium yield of $\text{SO}_3$?
- A1, 2 and 3
- B1 and 2 only
- C1 only
- D2 and 3 only