oxidationreduktionsförhållandena

Oxidationreduction, often shortened to redox, refers to a type of chemical reaction that involves the transfer of electrons between two chemical species. In a redox reaction, one species loses electrons, an process called oxidation, while another species gains electrons, a process called reduction. These two processes always occur simultaneously. It is impossible for oxidation to occur without reduction, and vice versa.

The term "oxidation" originally referred to reactions involving oxygen, as oxygen is a strong oxidizing agent. However, the definition has been expanded to include any process where a substance loses electrons, regardless of whether oxygen is involved. Similarly, "reduction" originally meant the removal of oxygen, but now refers to the gain of electrons.

Key concepts in redox reactions include oxidizing agents and reducing agents. An oxidizing agent is a substance that accepts electrons from another substance, thereby causing that substance to be oxidized. The oxidizing agent itself is reduced in the process. Conversely, a reducing agent is a substance that donates electrons to another substance, causing that substance to be reduced. The reducing agent itself is oxidized. Examples of redox reactions are abundant in chemistry and biology, including combustion, corrosion of metals, photosynthesis, and cellular respiration. Understanding redox reactions is fundamental to many areas of chemistry and its applications.