When electrons are lost from an atom, which process occurs?

When electrons are lost from an atom, the process that occurs is oxidation. Oxidation refers to the reaction in which an atom, ion, or molecule loses electrons, resulting in an increase in oxidation state. This loss of electrons can happen during various chemical reactions, including redox reactions, where one species is oxidized and another is reduced simultaneously.

In the context of electrochemistry, understanding oxidation is crucial, especially when considering corrosion processes, battery functionality, and other electrochemical applications. For example, in the formation of rust, iron atoms are oxidized as they lose electrons, which leads to the formation of iron oxides.

The other processes mentioned can be distinguished from oxidation. Reduction involves the gain of electrons, neutralization typically refers to the reaction between an acid and a base resulting in the formation of water and a salt, and combination involves the joining of two or more substances to form a single product. These distinctions are essential in the study of chemistry and electrochemistry.