Oxidizing and reducing agents

Oxidizing Agent

An oxidizing agent is a substance that causes another substance to undergo oxidation by accepting electrons itself. In other words, it is reduced while causing another substance to undergo oxidation.

Reducing Agents

A reducing agent is a substance that causes another substance to undergo reduction by donating electrons itself. In other words, it is oxidized while causing another substance to undergo reduction.

Example

In the reaction between copper and silver nitrate, silver nitrate acts as an oxidizing agent and copper acts as a reducing agent, because silver nitrate causes copper to lose electrons and undergo oxidation, while silver nitrate itself is reduced.

Equation

Cu + 2AgNO$_3$ → Cu(NO$_3$)$_2$ + 2Ag

Cu = Reducing agent (oxidation occurs in copper) AgNO$_3$ = Oxidizing agent (reduction occurs in silver nitrate)