How physical properties are important for identifying unknown substances

Every characteristic property is unique to one given substance. Scientists use characteristic properties to identify an unknown substance. Characteristic properties are used because the sample size and the shape of the substance does not matter.

Explanation:

A characteristic property is a chemical or physical property that helps identify and classify substances. The characteristic properties of a substance are always the same whether the sample being observed is large or small. Examples of characteristic properties include freezing/melting point, boiling/condensing point, density, viscosity and solubility.

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