* Physical Change: A change in the form or appearance of a substance, but not its chemical composition.

* Chemical Change: A change that results in the formation of new substances with different chemical properties.

When you color paper, you are simply adding a layer of colored material (like pigment or dye) to the surface. The paper itself doesn't change its chemical makeup. You could potentially remove the color and have the original paper back.

Here are some examples of chemical changes that would alter the paper's composition:

* Burning paper: This creates ash, carbon dioxide, and other substances, changing the paper's chemical composition.

* Treating paper with bleach: This would break down the paper's molecules, changing its color and potentially weakening its structure.

Let me know if you have any more questions!