Chapter 2: Properties of matter
WHAT IS MATTER?
Matter-anything that has mass and takes up space
Mass-amount of matter that an object contains
Matter with a uniform and definite composition is called a
substance.
All examples of a particular substance have the same physical
properties.
Physical property-a quality or condition of a substance that can
be observed without changing the substance’s composition.
Ex. Color, solubility, odor, hardness, density, melting point,
boiling point
What are the three states of matter?
Solid-matter that has a definite shape and volume
Liquid-matter that flows, has a fixed volume, and takes the
shape of its container
Gas-matter that takes both the shape and volume of its container
Physical change-an alteration to a material without changing its
composition
 Cutting, grinding, bending, dissolving, melting,
condensing, cracking
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 Changing the temperature of a substance can also
cause a physical change
 Freezing water
 Melting ice
 Boiling water to steam
MIXTURES
What is a mixture?
Mixture-a physical blend of two or more substances
There are 2 basic types of mixtures:
 Homogeneous mixture-has a completely uniform
composition
o This is also called a solution
 Heterogeneous mixture-not uniform in composition
Phase-any part of a system with uniform composition
o a homogeneous mixture would consist of a single phase
o a heterogeneous mixture would consist of 2 or more phases
Element-the simplest form of matter that can exist under normal
laboratory conditions
Each element is represented by a chemical symbol, usually
consisting of the first one or two letters of the element’s name.
Compound-substances that can be separated into simpler
substances only by chemical means
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CHEMICAL REACTIONS
Chemical reaction-the changing of substances to other
substances by the breaking of bonds in reactants and the
formation of bonds in products
Reactants-the starting substances
Products-the substances formed
Example: CuCl2 + Al  AlCl3 + Cu
Reactants
Products
The ability of a substance to undergo a chemical reaction and to
form new substances is called a chemical property.
How can you tell if a chemical reaction has occurred?
There are a few clues:
1) Energy is always is always absorbed or given off in
chemical reactions
a. This is not limited to chemical reactions-heat can be
released or absorbed in physical changes too
2) a change in color or odor or the production of a gas or a
solid from a liquid
a. this too, is not just in chemical reactions-for
example, when water boils, it changes from a liquid
to vapor, but this is only a physical change
3) Irreversibility
a. Chemical changes are often times difficult to
reverse
b. Physical changes however can be reversed-for
example, water can be frozen to form ice, then
melted again back to water
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