Q. Explain about Oxidation reduction potential?

The tendency of a substrate to accept or donate electrons is termed its redox potential (Eh). When a substrate loses electrons, the substrate is oxidized while a substrate that gains electrons becomes reduced. Therefore, a substance that readily gives up electrons is a good reducing agent, while one that readily takes up electrons is a good oxidizing agent. In the equation below, this is represented in its most general form to include the many redox reactions, which also involve protons and have the overall effect of transferring hydrogen atoms

Where n is the number of electrons, e, transferred.

When electrons are transferred from one compound to another, a potential difference is created between the two compounds. This difference may be measured by use of an appropriate instrument and expressed as millivolts (mv). It can be measured against an external reference by an inert metal electrode, usually platinum. The more highly oxidized a substance, the more positive will be its electrical potential, and the more highly reduced a substance, the more negative will be its electrical potential.