The Contact process is employed to change sulfur dioxide into sulfur trioxide. Vanadium(V) oxide acts as the catalyst in this process. $2\text{SO}_2\text{(g)} + \text{O}_2\text{(g)} \rightarrow 2\text{SO}_3\text{(g)}$ The forward reaction in this equilibrium gives out heat. Which of the statements about this process are correct?
- A1 and 2
- B1 and 3
- C2 and 4
- D3 and 4