Vanadium(V) oxide, V2O5\text{V}_2\text{O}_5V2O5, acts as a catalyst in the Contact Process. Which of the following equations represents the step in the Contact Process in which vanadium is reduced?
SO2+V2O5→SO3+2VO2\text{SO}_2 + \text{V}_2\text{O}_5 \rightarrow \text{SO}_3 + 2\text{VO}_2SO2+V2O5→SO3+2VO2
SO3+2VO2→SO2+V2O5\text{SO}_3 + 2\text{VO}_2 \rightarrow \text{SO}_2 + \text{V}_2\text{O}_5SO3+2VO2→SO2+V2O5
2VO2+12O2→V2O52\text{VO}_2 + \frac{1}{2}\text{O}_2 \rightarrow \text{V}_2\text{O}_52VO2+21O2→V2O5
V2O5→2VO2+12O2\text{V}_2\text{O}_5 \rightarrow 2\text{VO}_2 + \frac{1}{2}\text{O}_2V2O5→2VO2+21O2
