Physical Properties
* Definition: Characteristics that can be observed or measured without changing the substance's chemical composition.
* Examples:
* Color: The appearance of a substance (e.g., blue, green, red)
* Odor: The smell of a substance (e.g., sweet, sour, pungent)
* Density: The mass per unit volume of a substance (e.g., water has a density of 1 g/mL)
* Melting point: The temperature at which a solid changes to a liquid
* Boiling point: The temperature at which a liquid changes to a gas
* Solubility: The ability of a substance to dissolve in another substance (e.g., sugar dissolves in water)
* Hardness: Resistance to scratching or indentation (e.g., diamond is very hard)
* Conductivity: The ability to conduct heat or electricity (e.g., copper is a good conductor)
* State of matter: Whether a substance is a solid, liquid, or gas at a given temperature and pressure.
* Key point: Physical changes do not alter the chemical makeup of a substance.
Chemical Properties
* Definition: Characteristics that describe how a substance interacts with other substances to form new substances. These interactions involve changes in the chemical composition.
* Examples:
* Flammability: The ability of a substance to burn in the presence of oxygen (e.g., wood is flammable)
* Reactivity: The tendency of a substance to undergo chemical reactions (e.g., sodium is highly reactive with water)
* Corrosion: The gradual wearing away of a substance by chemical reactions (e.g., rusting of iron)
* Combustibility: The ability of a substance to react with oxygen to produce heat and light (e.g., burning wood)
* Acidity/Basicity: The degree to which a substance is acidic or basic (e.g., lemon juice is acidic, baking soda is basic)
* Key point: Chemical changes result in the formation of new substances with different properties.
In Summary:
Think of it this way:
* Physical properties: How a substance *looks* and *behaves* on its own.
* Chemical properties: How a substance *reacts* with other substances.
Let me know if you would like more examples or have any other questions!
