Case-I : [Coke as reducing agent]
`ZnO+CrarrZn+CO,DeltaG^(@)` becomes lesser as the T is more then 1120K.
Case =II [CO as reducing agent]
`ZnO+CO_(2)rarrZN+CO,DeltaG^(@)` becomes lesser when the T is more than 1323K.
`rarr` The value of `DeltaG^(@)` is negative for a raction to occur.
`rarr` In the equation (1) `DeltaG^(@)` becomes negative at low temperture-so equation (1) is feasible i.r. C is a better reducing agent for ZnO.s
