Here's why:

* Physical Properties: These are characteristics of a substance that can be observed or measured without changing the substance's chemical composition. Examples include:

* Color: The visual appearance of the substance.

* Density: The mass per unit volume.

* Melting Point: The temperature at which a solid turns into a liquid.

* Boiling Point: The temperature at which a liquid turns into a gas.

* Hardness: The resistance to scratching or indentation.

* Conductivity: The ability to conduct heat or electricity.

* Solubility: The ability to dissolve in a solvent.

* Chemical Properties: These are characteristics of a substance that describe how it reacts with other substances. They are observed when the substance undergoes a chemical change. Examples include:

* Flammability: The ability to burn.

* Reactivity: The tendency to react with other substances.

* Corrosion: The tendency to be eaten away by chemicals.

Key takeaway: A physical property can be observed and measured without changing the substance's chemical makeup.