Matter
Part II
1
Pure Substances vs. Mixtures
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Pure Substances
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Made of either elements or
compounds that are
chemically bonded.
Cannot be separated by
physical means.
Glucose: C6H12O6
Table Salt: NaCl
Oxygen Gas: O2
Carbon Dioxide CO2
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Mixtures:
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Two or more substances
mixed together but not
chemically combined.
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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
2
Mixtures
Heterogeneous Mixture
Homogeneous Mixture
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, CoolAid drink, milk, toothpaste
3
Organizing Concepts…
MATTER
PURE
SUBSTANCE
ELEMENTS
COMPOUNDS
MIXTURE
HETEROGENEOUS
HOMOGENEOUS
4
Choose a partner with the same learning
preference as you
Classify the following substances as:
Pure substance, heterogeneous mixture, or
homogeneous mixture
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Gatorade
Milk Shake
Meat marinade
Gasoline
Dirt
Sulfur
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Helium gas
Sugar Crystals
Fruit Loops
Mashed Potatoes
Vinegar
Air
5
Physical Properties of Matter
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Can be observed without changing a substance into another
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Mass – amount of matter that something has

Volume – amount of space that something takes
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State of matter – physical forms in which a substance can exist
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Melting point – temperature at which a substance changes from solid to
liquid
Boiling point – temperature at which a substance changes from liquid to
gas
Freezing point – temperature at which a substance changes from liquid
to solid
Density – the mass of a substance compared to its volume
d= m
v
6
State of Matter

Determined by the attraction between the particles of a substance, their rate of
movement and pressure change.

Matter changes from one state to another when its energy changes (either
loses or gains energy)

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Temperature is a measure of the speed (energy) of the particles of matter
 Increasing the temperature (energy) of a solid, causes it to change to liquid
(melting).
 Increasing the temperature (energy) of a liquid, causes it to change to gas
(vaporizing).
 The inverse process is also true
http://www.chem.purdue.edu/gchelp/atoms/states.html
State
Volume
Shape
Molecules
Solid
Definite
Definite
Vibrate
Liquid
Definite
Indefinite
Slide
Gas
Indefinite
Indefinite
Bounce
Plasma
Indefinite
Indefinite
Electrons split apart
7
Density
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Ratio between the mass and volume of a
substance
An object will only float on a liquid if its density
is lower than the density of the liquid
Predict which objects will float on water:
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dry sponge, small rock, large rock, wood block,
pencil, oil, ball of modeling clay, modeling class
shaped like a bowl, whole lemon, peeled lemon.
You will find out the correct answers by doing a
density lab
8
Chemical Properties of Matter

Describe a change that happens when two
substances react with each other
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Ex. rust, burning a match, candle or wood
9
The Periodic Table

Take the pretest
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Go to: http://peachstar.unitedstreaming.com/
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Select one of the following videos to watch:
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The Periodic Table: Reactions and Relationships (23:30)
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Simply Science: Periodic Table (27:04)
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(17:23) – quiz follows
© 1998 United Streaming
Discovering the Elements (57:12) – Two games follow
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© 1998 United Streaming
Physical Science Series: Atomic Structure and the Periodic Table
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© 1996 AIMS Multimedia
© 1996 United Learning
Take quiz
10
11
Periodic Table
Atomic Number
Mass Number
or Atomic Mass
Carbon
Element Name
6
C
Element Symbol
12.011
Guided Practice Assignment:
Look up the following elements in the periodic table. Draw a box like the one
above for each. Identify the atomic number and mass number.
Group 1: H, O, F
Group 3: Na, Mg, I
Group 2: N, Li, He
Group 4: Ca, Cl, K
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A few more…
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Q: Where does one put dirty dishes?
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Q: What weapon can you make from the
elements of potassium, nickel, and iron?
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A: In the “zinc”
A: KNiFe
Q: What is the difference between cooking and
chemistry?
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A: You should never lick the spoon
14
WEBQUEST
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Choose a partner whose favorite subject is the same as yours
(use the This Is Me inventory)
Follow the instructions on this website for your assignment:
http://web.buddyproject.org/web017/web017/
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Read all topics:
 History of the Periodic Table
 Inside an Atom
 Reading the Periodic Table
 Metals, Nonmetals, & Metalloids
Choose an element to do your final task and present to your
class:
 Element ADventure WebQuest
You will review and provide feedback to another group’s ad
presentation and will be graded on how you do your critique.
15
Your Critique
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Read the personal inventory of both members of
the group you are to critique
Write a letter to the group addressing the good
points and not-so-good points of their ad
Provide ideas on how they could improve their
ad
Assign the group a grade for their project
Go over your critique with the group explaining
your comments
Be honest, be fair, be mindful of other students’
feelings
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