Final answer:
Rusting is a redox reaction because it involves the transfer of electrons from iron to oxygen, with iron being oxidized and oxygen being reduced.
Step-by-step explanation:
Rusting is considered a redox reaction because it involves the transfer of electrons between iron and oxygen. Specifically, when iron rusts, it undergoes oxidation by losing electrons to oxygen, which is why option 3: "Electrons are transferred from iron atoms to oxygen atoms" is the correct choice. The iron atoms are oxidized as they lose electrons and form iron oxides, which are commonly seen as rust, while the oxygen atoms are reduced as they gain electrons.
The rusting of metals, such as iron, is considered a redox reaction because electrons are transferred between atoms. In the case of rusting, the transfer of electrons occurs from the iron atoms to the oxygen atoms. This process leads to the formation of iron oxide, or rust.
The oxidation step occurs when the iron atoms lose electrons and are oxidized, while the reduction step occurs when the oxygen atoms gain electrons and are reduced. The overall reaction can be represented as:
4Fe + 3O2 → 2Fe2O3