Is a boiled egg an example of chemical change?

* The protein structure changes: The heat from boiling causes the proteins in the egg white and yolk to denature. This means the long protein chains unfold and rearrange, forming new bonds. This is why the egg white becomes solid and opaque, and the yolk changes texture.

* Irreversible change: Once the proteins have denatured, they cannot easily be returned to their original state. You can't "unboil" an egg.

* New substances form: The chemical bonds and structures of the egg proteins are permanently altered, leading to the formation of new substances with different properties.

While you might think of boiling as just a physical change (heating something up), the changes to the egg's composition demonstrate that a chemical change is also occurring.