* Physical Changes: Alter the form or appearance of a substance but not its chemical composition.

* Examples: Cutting, bending, melting, freezing, boiling.

* Chemical Changes: Result in the formation of new substances with different chemical properties.

* Examples: Burning, rusting, cooking.

When you shorten a metal, you are simply changing its shape or size. The metal itself remains the same chemically. The atoms and molecules that make up the metal are not altered.

Let me know if you'd like more examples!