Q. Which will reduce zinc oxide to zinc?

 3071  221 AMUAMU 2004 Report Error

Solution:

Magnesium is placed above zinc in electrochemical series ie, its reduction potential is less than zinc so, it is more electropositive than zinc and it is also better reducing agent then zinc therefore, Mg will reduce zinc oxide to zinc.

While the reduction potential of and are higher than so, they cannot reduce zinc oxide to zinc.
The substances which have lower reduction potentials are stronger reducing agents while those which have higher reduction potentials are stronger oxidising agents.