* 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 heat sulfur, you are changing its state from solid to liquid. The sulfur molecules themselves remain the same. It's simply a change in how they are arranged and how they move.

Here's a breakdown:

* Solid Sulfur: The sulfur atoms are tightly packed in a crystalline structure.

* Liquid Sulfur: The sulfur atoms are still sulfur atoms, but they have more energy and can move more freely, breaking the rigid structure.

Important Note: If you continue to heat sulfur to very high temperatures (above its boiling point), it will change into a vapor, which is still a physical change. However, if you heat sulfur in the presence of oxygen, it will undergo a chemical change, forming sulfur dioxide gas (SO2). This is a chemical change because you are creating a new substance with different properties.