How does rust work to eat away a metal?

Question

Where does rust come from? How does it begin to form and why only on certain metals?

In: Chemistry

Answer 1

Rust is a chemical reaction. Oxygen atoms combine with iron atoms to form iron oxide. It doesn’t eat away metal, it *is* the metal, just in a different form. The iron changes properties due to the bond with oxygen, causing it to become flaky and brown etc. This is why there are pits left when rust is cleaned away. The metal that used to be in the pits is the rust that was removed.