Question

Why is the reduction of a metal oxide easier if the metal formed is in liquid state at the temperature of reduction?

Answer 1

Reduction of metal oxide

The entropy is higher if the metal is in liquid state than when it is in solid state.
The value of entropy changes $\Delta S$ of the reduction process is more positive when the metal formed is in liquid state and the metal oxide being reduced is in solid state.

Since we know,

${\Delta }_r{G}^{\Theta }=\Delta H^{\Theta }-T\Delta S^{\Theta }$

Thus, if $\Delta S$ become more positive the value of ${\Delta }_r{G}^{\Theta }$ becomes more negative and the reduction becomes easier.

Hence, due to this, the reduction of a metal oxide is easier if the metal formed is in liquid state.