What is the definition of a reducing agent?

A reducing agent is defined as a substance that donates electrons to another species during a chemical reaction. By giving up its electrons, the reducing agent causes the reduction of the other substance, which gains those electrons. This transfer of electrons results in the reducing agent itself being oxidized.

In the context of chemical reactions, understanding the role of reducing agents is essential because they drive processes such as redox (reduction-oxidation) reactions that are vital in many applications, including water treatment. By donating electrons, reducing agents can help remove contaminants from water, making it cleaner and safer for consumption.

The other options do not accurately describe the function of a reducing agent. While some substances may easily receive electrons or maintain chemical balance, these characteristics do not define a reducing agent's primary role in oxidation-reduction reactions. Similarly, being neutral in a reaction does not pertain to the behavior of a reducing agent, as reducing agents are actively involved in the transfer of electrons.