Physical and Chemical Properties of Matter - SS1 Chemistry Lesson Note

Properties of matter describe the characteristics and behaviour of substances. They help us identify, distinguish, and classify different types of matter. Properties can be broadly categorised into two main types: physical properties and chemical properties. 

Physical Properties:

Physical properties are characteristics that can be observed or measured without changing the chemical composition or identity of a substance. They are related to the physical state, appearance, and behaviour of matter. Some key examples of physical properties include:

1. Colour: The visual appearance or hue of a substance.
2. Odour: The characteristic smell of a substance.
3. Texture: The feel or surface characteristics of a substance, such as smooth, rough, or grainy.
4. Density: The mass per unit volume of a substance.
5. Melting Point: The temperature at which solid changes to a liquid.
6. Boiling Point: The temperature at which a liquid changes to a gas.
7. Solubility: The ability of a substance to dissolve in a solvent.
8. Conductivity: The ability of a substance to conduct heat or electricity.
9. Magnetism: The property of being attracted to or repelled by a magnet.
10. Hardness: The resistance of a substance to being scratched or dented.

Physical properties can be measured or observed without altering the chemical composition of a substance. They provide information about how a substance behaves under different conditions and can be used for identification, classification, and characterization.

Chemical Properties:

Chemical properties describe how a substance undergoes chemical changes or reactions, involving the transformation of one or more substances into new substances with different properties. Chemical properties are observed through the behaviour of a substance during a chemical reaction. Some key examples of chemical properties include:

 

1. Flammability: The ability of a substance to burn or ignite.
2. Reactivity: The tendency of a substance to undergo chemical reactions.
3. Oxidation: The ability of a substance to react with oxygen or undergo oxidation-reduction reactions.
4. Stability: The resistance of a substance to undergo chemical changes.
5. Acidity/Basicity: The ability of a substance to act as an acid or a base.
6. Toxicity: The degree to which a substance is harmful to living organisms.

 

Chemical properties are crucial for understanding the reactivity and behaviour of substances during chemical reactions. They help predict and explain the formation of new substances, changes in energy, and the overall outcome of chemical processes.

Physical properties, such as boiling point or solubility, can provide clues about the chemical behaviour and composition of a substance. Chemical properties, on the other hand, can be influenced by physical conditions such as temperature, pressure, or the presence of catalysts.

Understanding and studying the physical and chemical properties of matter are essential for various scientific disciplines, including chemistry, materials science, and engineering. These properties allow scientists to characterise, manipulate, and utilise different substances for a wide range of applications.