Is the rusting of iron a physical change or a chemical change?

Rusting of iron is a chemical change because it involves a reaction between iron and oxygen, resulting in the formation of a new substance, iron oxide (rust). During this process, the iron atoms chemically bond with oxygen from the air, altering the iron's chemical composition. The rusted iron has different properties, such as color, texture, and strength, from the original iron, making it an irreversible transformation. This reaction cannot be undone simply by physical means, confirming that rusting is a chemical change.