What does a reducing agent do in a chemical reaction?

In a chemical reaction, a reducing agent is characterized by its ability to lose electrons. When a reducing agent loses electrons, it facilitates the reduction of another substance by providing those electrons. This process is essential in redox (reduction-oxidation) reactions, where one species is reduced (gains electrons) while the other is oxidized (loses electrons).

By losing electrons, the reducing agent undergoes oxidation, which means it effectively increases its oxidation state. This transformative role is vital for driving many chemical reactions in analytical chemistry and other fields. For instance, in organic chemistry, reducing agents such as lithium aluminum hydride (LiAlH4) or sodium borohydride (NaBH4) are employed to reduce carbonyl compounds to alcohols by donating electrons to them.

This loss of electrons is what distinguishes reducing agents from other agents in chemical reactions. While the action of gaining electrons or forming precipitates pertains to different roles, those don't define the role of a reducing agent. Hence, the accurate description of a reducing agent is one that loses electrons, facilitating the reduction process within a reaction.