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Classification and Properties of Matter

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Advanced Placement Chemistry

Lesson Plan #1

1 class period

Classification and Properties of Matter

States of Matter


    • No fixed volume

    • No fixed shape

    • Conforms to the volume and shape of container

    • Can be compressed to a smaller volume

    • Can expand to a larger volume


    • Has a distinct volume independent of its container

    • No specific shape

    • Assumes shape of the portion of the container it occupies.

    • Can not be compressed to any appreciable extent.


    • Has definite shape

    • Has definite volume

    • It is rigid

    • Can not be compressed to any appreciable extent.

On the Molecular Level:


    • Molecules are far apart

    • Moving at high speeds

    • Colliding repeatedly with each other and walls of container


    • Molecules packed more closely together

    • Still move rapidly

    • Allowed to slide over each other

    • Liquids pour easily


    • Molecules held tightly together

    • Usually in definite arrangements

    • Molecules can wiggle only slightly

    • Solids have rigid shapes.

Pure Substances and Mixtures

Pure substance

    • Has fixed composition

    • Has distinct properties


    • Substances that cannot be decomposed into simpler substances

    • Composed of only one kind of atom


    • Composed of two or more elements

    • Contain two or more kinds of atoms


    • Combinations of two or more substances in which each substance retains its own chemical identity and its own properties

    • Two types of mixtures

    • Heterogeneous mixtures

    • Homogeneous mixtures

Heterogeneous mixtures

    • Do not have the same composition, properties, and appearance throughout the mixture.

    • Examples: sand, rocks, and wood

Homogeneous mixtures

    • Uniform throughout the mixture

    • Examples: air, salt, sugar, and many other substances dissolved in water to form homogeneous mixtures.

    • Also called solutions

    • Air is a gaseous solution; gasoline is a liquid solution; brass is a solid solution

Separation of Mixtures

Here is a way to determine what a substance is.



Is it uniform throughout?

No                   Yes

Heterogeneous    Homogeneous




Can it be separated by physical means?

NO                YES

Pure Substance homogeneous mixture (solution)




Can it be decomposed into other substances by chemical processes?

NO                         YES

Element                 Compound


    • 122 known at present

    • vary widely in abundance

    • over 90% of Earth's crust consists of only 5 elements:

    • oxygen

    • silicon

    • aluminum

    • iron

    • calcium

    • in contrast, just three elements account for over 90% of the mass of the human body

    • oxygen

    • carbon

    • hydrogen

    • symbol for each element consists of one or two letters, with the first letter capitalized (exception: three letters for elements in which name has not been uniformly adopted)


    • Law of constant composition (or the Law of definite proportions)

    • French chemist Joseph Louis Proust in about 1800

    • A pure compound has the same composition and properties regardless of its source

Properties of Matter

    • Every substance has a unique set of properties - characteristics that allow us to recognize it and to distinguish it from other substances

    • Physical properties - can be measured without changing the identity and composition of substance.

    • Examples: color, odor, density, melting point, boiling point, and hardness

    • Chemical properties - describe the way a substance may change or react to form other substances

    • Example is flammability, the ability of a substance to burn in the presence of oxygen

    • Intensive properties are useful in chemistry, can be used to identify substances

    • Examples are temperature, melting point, and density

    • Do not depend on the amount of sample being examined

    • Extensive properties

    • Depend on the quantity of the sample

    • Include measurements of mass and volume

    • Relates to the amount of substance present

Physical and Chemical Changes

    • Physical changes

    • Substance changes its physical appearance but not its composition

    • Example is evaporation of water

    • All changes of state (for example, from liquid to gas or from liquid to solid) are physical changes

    • Chemical changes

  • Also called a chemical reaction

  • Substance is transformed into a chemically different substance

  • Example: when hydrogen burns in air, it undergoes a chemical change in which it is converted into water