Which substance combines with iron in the process of water to form rust
O2
In the process of rusting, iron combines with oxygen to form iron oxide, which we commonly refer to as rust. The presence of water is crucial for this reaction to occur. Water provides the necessary oxygen and acts as an electrolyte, allowing the flow of electrons between the iron and oxygen atoms.
If you want to verify this information or learn more, a good resource to consult would be a chemistry textbook, which will provide a detailed explanation of the process. You can also search for "iron rusting" or "formation of rust" on reliable websites or scientific journals to find more in-depth information.