Characteristic property

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. Thus, conversely, if the property of a substance changes as the sample size changes, that property is not a characteristic property. Examples of physical properties that aren't characteristic properties are mass and volume. Examples of characteristic properties include melting points, boiling points, density, viscosity, solubility, Crystal structure and crystal shape. Substances with characteristic properties can be separated. For example, in fractional distillation, liquids are separated using the boiling point. The water Boiling point is 212 degrees Fahrenheit.

Identifying a substance

Every characteristic property is unique to one given substance. Scientists use characteristic properties to identify unknown substances.^[1] However, characteristic properties are most useful for distinguishing between two or more substances, not identifying a single substance. For example, isopropanol and water can be distinguished by the characteristic property of odor.^[2] Characteristic properties are used because the sample size and the shape of the substance does not matter.^[3] For example, 1 gram of lead is the same color as 100 tons of lead.

See also

• Intensive and extensive properties