THUS FAR WE HAVE REVIEWED MATTER AS
PURE SUBSTANCES.
NOW LETS DISCOVER MATTER AS MIXTURES
MATTER
PURE SUBSTANCE
ELEMENT
Carbon (C)
COMPOUND
H2O
MIXTURE
?
Classification
Matter
Has mass and takes up space
Substance
Define composition
Element
One kind of
atom
Compound
Two or more
kinds of atoms
Mixture
Variable Composition
Homogeneous
Evenly mixed
Heterogeneous
Unevenly mixed
Solution Process
A mixture is formed by two or more
elements or compounds that are physically
mixed together but not chemically joined.
example: salt and pepper
Mixture can be:
Homogeneous
Evenly mixed
Heterogeneous
Unevenly mixed
Classifying mixtures
Mixture is formed by two or more elements or compounds that
are physically mixed together but not chemically joined.
example: salt and pepper
The two types of Mixtures :
1) HOMOGENEOUS
Homogeneous
Evenly mixed
2) HETEROGENEOUS
Heterogeneous
Unevenly mixed
The Two Types of Mixture
1. Solution is a homogeneous mixture in which
one substances is dissolved in another
substance. It consists of a solute and solvent.
Solvent is the
substance in which
the solute is
dissolved
When sugar, a
solute and water a
solvent are mixed, a
water sugar solution
is formed.
Solute is the
substance
dissolved in
the solution.
The Two Types of Mixture (Cont.)
2. Suspension is a mixture of water with
non-dissolve material
Example sand and water
• Solute is the
substance
dissolved in the
solution
– Particles may be
ions, atoms, or
molecules
• Solvent is the
substance in which
the solute is
dissolved
Mixtures
Summary
Heterogeneous Mixture
(Suspension)
Homogeneous Mixture
(Solution)
Not evenly mixed
Evenly mixed
Individual components retain
their own properties
Properties of combined
components are usually different
than those of each component
Individual components can be
easily seen
Individual components can not
be easily seen
Can be easily separated
Not as easily separated
Ex.: salt & pepper mix, rocks,
cereal, bag of assorted candy
Ex. salt-water solution, tea,
kool-Aid drink
Solubility
Solubility is the amount of a substance that
can dissolve in 100 grams of
solvent at a given time.
• The ability of a solvent to dissolve a solute
depends on temperature and molecular structure.
• Like dissolve like:
• When the temperature of a liquid increases, The
solubility of the solvent increases.
SOLUBILITY GRAPH
Review: How matter is classified
Classifying Matter
Matter
Pure Substances
Mixtures
Homogeneous
Elements
Compounds
Tea, kool-aid
He, O
H2O, NaCl
Heterogeneous
Rocky Road ice
cream, muddy
water
Practice Problems
Determine whether each is a heterogeneous or homogeneous mixture:
1.
2.
3.
4.
5.
Tossed salad
Salt water
Kool-aid
Muddy water
OJ with pulp
Answers:
6. Tea
7. Banana nut bread
8. Pizza
9. Blood
10. Brass
1. He 2. Ho 3. Ho 4. He 5. He 6. Ho 7. He 8. He 9. He 10. Ho
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More review
Classify the following substances as:
Pure substance, heterogeneous mixture, or
homogeneous mixture
Gatorade
Homogenous mixture
Fruit Loops
Heterogeneous mixture
Gasoline
Pure substance
Dirt
Heterogeneous mixture
Sugar Crystals
Pure Substance
Air
Homogeneous mixture
Granite
Heterogeneous mixture
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1) We are studying CHEMISTRY, the study of
________and how it ________.
2) Matter is anything that has___ and takes up
___.
3) ___ are the basic building blocks of matter.
4) Matter can be classified as either a ___ or a
___.
5) Substances are either ___ or ___.
Answers:
1. matter, changes 2. mass, space 3. atoms 4. pure substance, mixture 5. elements, compounds
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MATTER AS MIXTURES
Mixtures are combinations of 2 or more substances
where each substance retains its individual properties.
HOW ARE MIXTURES LIKE COMPOUNDS?
HOW ARE MIXTURES DIFFERENT
FROM COMPOUNDS?
THEY ARE MADE FROM TWO
OR MORE SUBSTANCES
MIXTURES DO NOT FORM
CHEMICAL BONDS.
is
…a mixture that is the same throughout.
A homogeneous mixture has a
composition and properties that are
identical regardless of the sample
Ways to identify a homogeneous mixture:
 one phase
 uniformly mixed
 won’t settle out
 small particles
A SOLUTION is another name for a homogeneous mixture
is
… a mixture that is visibly different
throughout. Heterogenous mixtures have
a composition and properties that differ
in any given sample.
Ways to identify a heterogeneous mixture:
 not uniformly mixed
 more than one phase
 will settle out
 larger particles
HETEROGENEOUS MIXTURES
There are special types of heterogeneous mixtures:
• Suspensions-appear uniform when mixed but settle out.
–
–
–
–
Chocolate Quik
Muddy water
Pulpy oj
Oil & Vinegar dressing
• Colloids-appear uniform but they do not settle out. However,
their particles are too large to be classified as a homogeneous
solution.
–
–
–
–
Gelatin
Smoke
Fog
mayonnaise
Now, lets put it all together and determine how
to tell substances (compounds and elements)
from mixtures.
• Pure Substances
– Made of either elements or
compounds that are
chemically bonded.
– Cannot be separated by
physical means.
– When combined they take
on new properties different
from the original elements.
– Examples:
•
•
•
•
Glucose: C6H12O6
Table Salt: NaCl
Oxygen Gas: O2
Carbon Dioxide CO2
• Mixtures:
– Two or more substances mixed
together but not chemically
combined.
• Tea = Crushed Leaf + H2O
• Rocks = minerals + sediments +
organic matter
• Sugar Water = Sugar + H2O
– Each component retains its own
identity; it does not change into
something else.
– Can be separated by physical
means
– Examples:
• Sweet tea
• Trail mix
• Air (O2, N2, CO2, Ar)
Elements, Compounds, and Mixtures
Two of the descriptions to the right apply to each bottle
below. Determine the appropriate descriptions.
a. Two types of
atoms evenly
mixed
b. Two types of
atoms chemically
combined
c. One type of atom
oxygen atoms
hydrogen
atoms
d. Two types of
atoms mixed
hydrogen
atoms
e. An element
f. A solution
g. A compound
h. A mixture
d&h
1_______
b&g
2_______
c&e
3_______
a&f
4_______
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