Physical Properties: Characteristics of a substance that can be measured without altering its chemical composition, such as mass, volume, and density.

Chemical Properties: Traits that can only be evaluated by changing the substance's chemical identity, indicating how a substance reacts with other substances.

Classification of Matter: Matter is categorized as either pure substances or mixtures.

• Pure Substances: Include elements and compounds.

• Mixtures: Can be homogeneous (uniform composition) or heterogeneous (non-uniform composition).

Law of Chemical Combination:

• Law of Conservation of Mass: In any chemical reaction, the total mass of reactants equals the total mass of products formed.

• Mass:Reactants=Products