Physical properties of matter are characteristics that can be observed or measured without changing the substance's chemical identity. These properties describe the physical state and appearance of matter and include:

• Color : The appearance or hue of a substance, which generally does not change with quantity (intensive property)

• Hardness : Resistance to deformation or scratching; varies among substances (e.g., diamond is very hard, graphite is soft)

• Malleability : Ability to be shaped or molded without breaking, such as metals being formed into thin sheets

• Solubility : The capacity of a substance to dissolve in a solvent without chemical change

• Electrical Conductivity : Ability to conduct electricity, important in metals like silver

• Density : Mass per unit volume, an intensive property that helps identify substances (e.g., gold has high density, water about 1 g/cm³)

• Melting Point and Boiling Point : Temperatures at which a substance changes state (solid to liquid, liquid to gas), useful for identification and purity assessment

• Odor : The smell of a substance, which is a physical characteristic

• State of Matter : Whether a substance is solid, liquid, or gas at a given temperature and pressure

Physical properties are further classified as:

• Intensive properties : Do not depend on the amount of matter (e.g., density, color, melting point)

• Extensive properties : Depend on the quantity of matter (e.g., mass, volume)

These properties allow scientists to describe, identify, and understand matter without altering its chemical composition