which of the following reduction reaction CANNOT
Question:

which of the following reduction reaction CANNOT be carried out with coke?

1. $\mathrm{Al}_{2} \mathrm{O}_{3} \rightarrow \mathrm{Al}$

2.  $\mathrm{ZnO} \rightarrow \mathrm{Zn}$

3. $\mathrm{Fe}_{2} \mathrm{O}_{3} \rightarrow \mathrm{Fe}$

4. $\mathrm{Cu}_{2} \mathrm{O} \rightarrow \mathrm{Cu}$

Correct Option: 1

Solution:

Reduction of $\mathrm{Al}_{2} \mathrm{O}_{3} \rightarrow \mathrm{Al}$ is carried out by electrolytic reduction of its fused salts.

$\mathrm{ZnO}, \mathrm{Fe}_{2} \mathrm{O}_{3} \& \mathrm{Cu}_{2} \mathrm{O}$ can be reduce by carbon.