Question:
Out of C and CO, which is a better reducing agent at 673 K?
Solution:
At $673 \mathrm{~K}$, the value of $\Delta \mathrm{G}_{\left(\mathrm{co}, \mathrm{CO}_{2}\right)}$ is less than that of $\Delta \mathrm{G}_{(\mathrm{c}, \mathrm{co})}$. Therefore, $\mathrm{CO}$ can be oxidised more easily to $\mathrm{CO}_{2}$ than $\mathrm{C}$ to $\mathrm{CO}$. Hence, $\mathrm{CO}$ is a better reducing agent than $\mathrm{C}$ at $673 \mathrm{~K}$.