A characteristic physical property is a characteristic property that can be determined without modifying the nature of a substance.
When the characteristic physical properties of a substance are observed, the nature of that substance remains unchanged. Thus, the substance may undergo a phase change to determine its melting point, but its molecular composition remains the same. The various physical properties can be determined with the naked eye or with measuring instruments such as thermometers and scales.
It should be noted that the characteristic properties must be determined at a precise temperature and pressure. In fact, a higher or lower temperature or pressure can alter the characteristic properties of a substance. For example, water boils at 100 °C at sea level, while it boils at 94 °C at an altitude of 1 600 m where atmospheric pressure is lower.
Here is a non-exhaustive list of various characteristic physical properties:
Road signage indicating melting point of water (left), paper indicating the acid-base character of a substance (centre), and magnet to determine the magnetic character of a substance (right).
