What chemical change occurs when a substance combines with oxygen, such as iron rusting?

When a substance combines with oxygen, it undergoes oxidation, which is the process that involves the transfer of electrons resulting in the formation of oxides. In the context of iron rusting, iron reacts with oxygen in the presence of moisture to form iron oxide, commonly known as rust. This reaction not only alters the chemical structure of the iron but also signifies that the iron has lost electrons due to the interaction with oxygen.

Oxidation is a crucial part of various chemical processes, especially when reactive metals are involved. In rusting, the oxidation of iron is central to the deterioration and weakening of its properties. It illustrates the broader concept of oxidation-reduction (redox) reactions, where oxidation refers specifically to the loss of electrons, and reduction refers to their gain.

In contrast, other terms like corrosion typically refer to the gradual destruction of materials, often metals, due to chemical reactions with environmental elements or substances but do not specifically denote the role of oxygen. Reduction involves gaining electrons, which is not what takes place in the rusting process. Combustion refers to a specific type of oxidation reaction that produces heat and light, typically involving hydrocarbons and oxygen, which differs from the rusting of iron. Thus, oxidation precisely describes the chemical change