What is oxidation?

They are the chemical reactions in which oxygen combines with other substances, forming molecules called oxides. This is particularly common in the world of metals, although by no means exclusive to them. In chemistry, oxidation is the chemical phenomenon in which an atom, molecule or ion loses one or more electrons, thus increasing its positive charge.

As oxygen is an element that usually accepts these electrons, these types of reactions were called reduction-oxidation reactions, oxidation-reduction reactions or redox reactions, but it is also important to clarify that there may be redox reactions in which oxygen participates. Let’s take into account that the name oxygen comes from the Greek oxys, “acid”; and genos, “producer”: that is, oxygen is so called because it corrodes metals, just as acid does.

Most cases of oxidation involve oxygen, but it can also occur in its absence. And similarly, oxidation and reduction always occur together and simultaneously. They always involve two elements exchanging electrons:

The oxidizing agent. It is the chemical element that captures the transferred electrons, that is, it receives them and increases their negative charge. This is called having a lower oxidation state, or in other words, being reduced.

The reducing agent. It is the chemical element that gives up or loses the transferred electrons, increasing its positive charge. This is called having a higher oxidation state, or in other words, being oxidized.

The oxidizing agent is reduced by the reducing agent, as the reducing agent is oxidized by the oxidizing agent. In this way, we have to oxidize is to lose electrons, while to reduce is to gain electrons.

These processes are common and everyday, in fact they are essential for life: living beings obtain chemical energy thanks to similar reactions, such as the oxidation of glucose. Let’s carry out the following experiment and see how the oxidation process can be observed in a common object.