Akzeptors

An acceptor is a substance that accepts a specified entity in a chemical process. The term is used across several fields to describe species that gain electrons, protons, or electron pairs during a reaction. In redox chemistry, an acceptor is an oxidizing agent that takes up electrons from another species. Common examples include molecular oxygen in aerobic respiration and permanganate ions in various oxidative titrations.

In acid–base chemistry, a proton acceptor is a base as defined by Bronsted-Lowry theory. It accepts a proton from an acid, with the conjugate acid formed on the other side. Conventional bases such as hydroxide, ammonia, and amines serve as proton acceptors in solution.

In Lewis theory, an acceptor is a Lewis acid that accepts an electron pair. This broad concept covers many metal cations and covalent reagents such as boron trifluoride and aluminum chloride, as well as larger systems that form adducts with donors.

Biological systems use acceptors to carry electrons or hydrogens during metabolism. NAD+ and FAD act as mobile electron acceptors, becoming NADH and FADH2; oxygen often serves as the terminal electron acceptor in aerobic respiration.

In solid-state chemistry, acceptor dopants introduce acceptor levels in semiconductors, creating holes that enhance p-type conductivity. Typical examples include boron in silicon or gallium in germanium.