The characteristic of a substance that can be measured or observed without changing the identity of the material is called a physical property.

Here are some examples of physical properties:

* Color: The appearance of a substance to the human eye.

* Density: The mass per unit volume of a substance.

* Melting point: The temperature at which a substance changes from a solid to a liquid.

* Boiling point: The temperature at which a substance changes from a liquid to a gas.

* Hardness: The resistance of a solid to scratching or indentation.

* Conductivity: The ability of a substance to conduct electricity or heat.

* Solubility: The ability of a substance to dissolve in a solvent.

* Odor: The smell of a substance.

Important note: Physical properties can be used to identify and classify substances. However, it's important to remember that a single physical property may not be enough to definitively identify a substance.