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3 KINDS OF MATTER
Elements
Compounds
Mixtures
Elements
All (living and nonliving) of the different
kinds of matter in the universe is made
from about 100 different substances,
called elements.
Elements are called the building blocks of
matter because all matter is composed of
elements.
Elements
 Elements are the simplest pure substance.
An element can not be changed into a simpler
substance by heating or any chemical process.
 The smallest particle of an element that has the
properties of that element is called an atom.
An atom is the basic building block of matter.
 There are more than one hundred known
elements in the universe listed on the periodic
table of elements.
These elements combine in such a way to create
millions of compounds.
Elements
In 1813, a system
of representing
elements with
symbols was
introduced.
 Each symbol consists of one
or two letters.
 Two letters are needed for a
chemical symbol when the
first letter of that element’s
name has already been
used.
Common Elements
Aluminum
Bromine
Calcium
Carbon
Gold
Helium
Hydrogen
Nitrogen
Al
Br
Ca
C
Au
He
H
N
Compounds
Compounds
A compound is a substance made of two
or more different kinds of elements
chemically combined in a specific ratio.
Each compound is represented by a
formula that uses symbols to identify
which elements are present.
A formula shows the ratio of elements in
the compound.
H2O – ratio of Hydrogen is 2:1 Oxygen
Compounds and Mixtures
 Most of the matter around
you is in the form of
compounds or mixtures.
 Water, carbon dioxide, salt,
vinegar, baking soda, lye,
sugar, gasoline, and bleach
are all chemical
compounds.
The symbols make up the formula. A
formula is just chemical shorthand for the
compound.
Count the capital letters to find the
number of elements in any compound

The subscript lets us know how many
atoms are present.
Practice: How many elements are in the
following?
Glucose C6H12O6
 Carbon Dioxide
CO2
Mixtures and
compounds differ
in two ways…
Substances in a mixture keep
their individual properties.
Parts of a mixture are not
necessarily present in specific
ratios.
By asking these questions scientists can classify
matter into:
 Mixtures – two or more substances that are not
chemically combined with each other and can be
separated by physical means. The substances in
a mixture retain their individual properties.
Solutions – a special kind of mixture where one
substance dissolves in another.
 Elements – simplest form of pure substance.
They cannot be broken into anything else by
physical or chemical means.
 Compounds – pure substances that are the
unions of two or more elements. They can be
broken into simpler substances by chemical
means.
Element, Compound, or Mixture?
Rocks
Element, Compound, or Mixture?
Rocks
Element, Compound, or Mixture?
Copper
Element, Compound, or Mixture?
Copper
Element, Compound, or Mixture?
Jelly Beans
Element, Compound, or Mixture?
Jelly Beans
Element, Compound, or Mixture?
Table Sugar
Element, Compound, or Mixture?
Table Sugar
Element, Compound, or Mixture?
Diamond
Element, Compound, or Mixture?
Diamond
Element, Compound, or Mixture?
Tea
Element, Compound, or Mixture?
Tea
Element, Compound, or Mixture?
Salt
Element, Compound, or Mixture?
Salt
Element, Compound, or Mixture?
Neon Gas
Element, Compound, or Mixture?
Neon Gas
Element, Compound, or Mixture?
Salad
Element, Compound, or Mixture?
Salad
Element, Compound, or Mixture?
Pure Water
Element, Compound, or Mixture?
Pure Water
Element, Compound, or Mixture?
Aluminum
Element, Compound, or Mixture?
Aluminum
Element, Compound, or Mixture?
Lemonade
Element, Compound, or Mixture?
Lemonade
Element, Compound, or Mixture?
Silver
Element, Compound, or Mixture?
Silver
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