Out of C and CO, which one is the reagent of your choice for the reduction of ZnO? Why?

Explanation

From the Ellingham diagram, it is seen that `("CO,CO"_(2))` line always lies above the `("Zn, ZnO")` line. Thus at any temperature the `Delta_(f)G^(@)` of formation of ZnO from Zn. Therefore CO cannot be used in the reduction of ZnO. However, `("C,CO")` line above 1180K and `("C,CO"_(2))` line above 1270K lie below `(Zn, ZnO)` line. So, above 1180 K, `Delta_(f)G_("(C,CO)")^(@)` is more negative than `Delta_(f)G_("(Zn, ZnO)")^(@)`. Therefore above 1270 K, ZnO can be completely reduced by C to form elemental Zn. Hence C act as better reducing agent than CO in reducing ZnO.