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Matter
WHAT DO YOU KNOW
ABOUT STATES OF
MATTER?
• What are the three commonly known states of
matter?
• What is the gas, liquid and solid form of water?
• How does matter change state?
Watch this animation on states of matter (click “Play Video”):
Animation: States of Matter
http://teacher.scholastic.com/activities/studyjams/matter_states/
Scholastic
WHAT ARE STATES OF MATTER?
States of matter
are the
physical forms
a substance
can take.
There are three
common states
of matter: solid,
liquid, and gas.
Each of these
states is also
called a phase.
THE THREE COMMON
STATES OF MATTER
Most substances, like water, can exist in all three states.
An iceberg is made
of water in solid form.
This glass
contains liquid
water.
A cloud is made of
water vapor, a type
of gas.
SOLIDS
• Solids have a definite
shape and volume, or
amount of space an
object takes up.
The particles
that make up a
solid are packed
tightly and held
together by
strong forces.
• Solid particles vibrate in
place but cannot move
from their position, which
is why solids maintain
their
rigid shape.
LIQUIDS
• Liquids have a definite
volume but not a definite
shape.
The particles
that make up a
liquid are spaced
farther apart and
are held together
by weaker forces
than solids.
• Liquid particles move
slightly, which allows
liquids to flow and take
the shape
of the container they are
in.
GASES
• Gases do not
have a definite volume
or shape.
The particles
that make up a
gas are fastmoving and are
held together by
extremely weak
forces.
• Gas particles move
freely and will expand to
fill a container of any
size or shape.
CHANGES OF STATE
• Matter can change from one
state to another.
•
Even though the physical form of the
matter changes, it remains the same
substance.
•
Changes of state occur when
thermal energy (heat energy) is
absorbed or released by a
substance.
WHAT ARE THE
CHANGES OF STATE?
GAS
SOLID
LIQUID
HOW DOES MATTER
CHANGE STATE?
Temperature
Changes of State
•
•
Thermal Energy Added
As heat
increases,
a substance
changes from
a solid to a
liquid, and
finally to a gas.
As heat
decreases,
a substance
changes from a
gas to a liquid,
and finally to
a solid.
DISCUSSION QUESTIONS
• How does pressure and temperature affect the state
of water, carbon dioxide, and hydrogen?
Use this interactive PBS Web site to find out:
www.pbs.org/wgbh/nova/zero/matt-flash.html.
• On Earth, we typically see gases, liquids, and solids.
a fourth
state of
at this Web site:
But is Learn
thereabout
a fourth
state
ofmatter
matter?
http://www.spaceweathercenter.org/amazing_plasmas/02/02.html
HANDS-ON SCIENCE
(No Lab Required)
This demo explores melting points.
Materials
chocolate chips, candy-coated chocolates, baggies, two mugs, water, thermometer
Directions
1. Place chocolate chips and candy-coated chocolate in separate bags.
2.
Place each bag of chocolate in a half-filled mug of room-temperature water.
3.
Your teacher will continue to increase the temperature in each mug by adding
boiling water a little at a time.
4.
As a class, monitor the temperature with a thermometer until the chocolate
starts to melt in the bag.
Conclusion
At what temperature does each type of chocolate start to melt?
Why do you think this is?
Solid: has definite shape and volume
Liquid: has definite volume but not
shape
Gas: does not have definite volume or
shape.
Physical Change: a change that
does not result in new substances.
Freezing point: temperature when
liquid changes to a solid:
water is 32 F or 0 C
Melting point: temperature when solid
changes to liquid
Boiling point: temperature when liquid
changes to a gas.
Water: 212 F… 100 C
Sublimation: changes from a solid to a
gas. Example: dry ice
Condenses: changes from gas to liquid
because it cools down. Example: water
on the outside of a can of pop.
Matter: has mass and takes up
space.
Mass: the amount of matter
something has
Volume: amount of space
something takes up
Weight: measure of the force
of gravity on an object’s
mass
Density: measurement of how
much matter is in an object.
Mass divided by volume
Physical Properties:
color
smell
freezing point
melting point
boiling point
density
solubility
Chemical Properties:
odor
color change: trees in autumn
oxidation
flammability
Ph (acid or base)
Physical Change: doesn’t change
what the substance is.
Can be reversed.
Examples: torn piece of paper;
mixing sugar and water
Chemical Change: causes a
chemical reaction and a new
substance is formed.
Cannot be reversed.
Examples: paper burned;
baking a cake
Law of Conservation of Mass:
Matter can never be created or
destroyed. All matter is present just
changes form.
Dmitri Mendeleev: known for
putting the periodic table together
as we know it today.
The Periodic Table of elements
organizes the elements based on
atomic number. There are approximately
100 elements. They are organized into 18 groups
and 7 periods.
Atoms
Atoms: the smallest parts of something
that can be identified.
a. Protons: positive charge/found in
the nucleus
b. Neutrons: neutral charge/found in
the nucleus
c. Electrons: negative charge/outside
the nucleus
d. Nucleus: in the center of the atom
Atomic Number: represents the
number of protons and electrons.
Atomic Mass: represents the
number of protons and neutrons.
If I use Carbon---the atomic number
is 6. That means carbon has 6
protons and 6 electrons. To find out
how many Neutrons there are plug
in the numbers: atomic mass is 12
which equals number of protons
and neutrons. If the protons are 6
then the neutrons are 6.
protons + neutrons = atomic mass
Element: a substance that cannot be split
into simpler substances. Made up of
only one kind of atom.
Examples: H, O, N, Cl
Mixture: any substance made of 2 or more
atoms that can be separated physically.
Examples: Tossed Salad, Chex Mix, Cereal
Solution: mixture where particles of
different substances are mixed evenly:
Example: Powdered fruit drinks
Compounds: matter made of 2 or more
different elements.
Examples: water: H2O & Table sugar:
C12H22O11
Molecule: any substance made of 2 or
more atoms.
Examples: Water:H2O & Table Salt: NaCl &
Ozone: O3
Simple Machines
Notes over Simple Machines
LEVER:
1. Fulcrum: the pivot point where it rotates
2. Effort/Force: a push or pull
3. Resistance/Load: an object being moved.
4. 3 Classes of levers:
a. 1st: Fulcrum in the middle: a crow bar, see-saw
b. 2nd Load in the middle: wheel barrel, nutcracker
c. 3rd Effort in the middle: broom, rake
5. M.A.= effort arm divided by resistance arm
Notes over Simple Machines
Wheel/Axle:
• The bigger the wheel compared to the axle
the easier the work.
Examples: car wheels, door knobs, skates, bike
tires
2. M.A.= Diameter of wheel divided by the
diameter of the axle
Notes over Simple Machines
Pulley:
• Fixed pulley: attached to something. No M.A.
But changes direction of effort.
2. Moveable pulley: moves with the object. Only
half as much effort is needed.
3. Block and Tackle pulley: used to lift heavy
objects. 2 pulleys are used.
4. M.A. is multiplied by the number of strands in
a pulley.
Notes over Simple Machines
Screw:
An inclined plane wrapped around a pole.
Examples:
Nut/bolt, jar lid, road around a mountain,
Notes over Simple Machines
Wedge:
An object that cuts separates things.
Examples:
Knife, door stop, ax, scissors, fork, tip of nail
Notes over Simple Machines
Inclined plane:
A flat sloped surface.
Examples:
Ramp, roof, staircase
Notes over Simple Machines
1. Simple Machines are used to reduce the force
needed to move an object while increasing the
distance over which the force is applied.
2. Friction will reduce the output of simple machines
or increase the amount of force needed.
3. Force needed to move an object can be reduced by
combining 2 or more simple machines to create a
compound machine.
4. The force required to lift an object by yourself is
equal to the weight of the object. BUT when you
use a simple machine the object can be lifted
with less force.
Newton’s Laws of Motion
NOTES
1. Newton’s 1st Law: an object at rest stays at
rest and an object in motion stays in motion
unless a force acts on it.
2. ALSO CALLED THE LAW OF INERTIA
FORCES:
a. Gravity: pulls/holds onto things
b. Friction: wears down, slows down, heats up when
2 objects come in contact with each other.
c. Air resistance
EXAMPLES: a book on the table, swing
NOTES
2. Newton’s 2nd Law: the greater the force the
greater the acceleration. The larger the mass
of the object the greater the force required to
accelerate or slow down the object.
EXAMPLES: empty/full grocery cart &
Diesel or small car
ACCELERATION: speeding up
FORCE: the push or pull on an object
NEWTONS: (N)the unit of force required to
accelerate an object. (1 kg-1 m per s2)
NOTES
3. Newton’s 3rd Law: For every action there is an
equal but opposite reaction.
EXAMPLES: firing a gun, rocket shooting
NOTES
Balanced forces: when 2 or more forces act on
the same object equally in opposite directions.
Unbalanced forces: unequal forces that act on an
object and change its motion.
Motion Graphs
Interpret The Graph Below:
Interpret The Graph Below:
The graph shows
an object which
is not moving (at
rest).
The distance
stays the same
as time goes by
because it is not
moving.
Interpret The Graph Below:
Interpret The Graph Below:
The graph shows
that the objects
distance increases
as time passes.
The object is moving
and so it has
velocity.
The straight line
shows it is a
constant (not
changing).
Interpret The Graph Below:
Interpret The Graph Below:
Just like the
previous
graph, this
graph shows
an object
moving with
constant
velocity
Interpret The Graph Below:
Interpret The Graph Below:
The curve in the
graph shows
that the objects
velocity is
changing as time
passes.
This is
acceleration.
Interpret The Graph Below:
Interpret The Graph Below:
In the first part of
the graph the object
is moving with
constant velocity.
In the second part of
the graph the object
is at rest (not
moving).
In the third part the
object is again
moving with
constant velocity.
Interpret The Graph Below:
Interpret The Graph Below:
The graph shows
that the objects
velocity does not
change as time
passes.
It shows constant
velocity.
Interpret The Graph Below:
Interpret The Graph Below:
The graph shows
that the objects
velocity is
increasing as time
passes – it is
accelerating.
The straight line
shows that it is
constant
acceleration.
Click here for more review:
http://www.usoe.k12.ut.us/curr/sci
ence/sciber00/8th/forces/sciber/int
ro.htm
Heat
Temperature: the measure of how hot or
cold something is.
Thermometer: a device used to measure
the temperature of an object.
Heat: energy that is based on the
temperature and mass of an object.
Absolute Zero: the lowest possible
temperature.
Kelvin: 0
Celcius: -273
Fahrenheit: -459.7
Celcius: temperature scale based
on freezing & boiling points of
water.
Freezing: 0
Boiling: 100
Fahrenheit: a temperature scale
based on water freezing.
Freezing: 32
Boiling: 212
Kelvin: a temperature scale based
on absolute zero.
Freezing: 272
Boiling: 373
Conduction: transfers heat energy
through direct contact.
Conductors: materials that allow
heat to pass easily.
Examples: water, metals
Convection:
Transfer of heat energy in a liquid or
gas in a circular motion.
Examples: oven, heater in house,
magma under the surface of the earth.
Radiation:
transfer of heat energy through the
emptiness of space.
Examples: sun, microwaves
Insulators:
material that does not allow heat to
pass through easily.
Examples: rubber, cloth, styrofoam,
wood
LIGHT
1.
2.
3.
4.
5.
6.
LIGHT VOCABULARY
Opaque: does not emit light (ex: cardboard)
Luminous: emits light (ex. Sun)
Transparent: light is able to pass through the
object. (ex: glass)
Translucent: some light can pass through (ex:
wax paper)
Refraction: bending of light waves (ex. Pencil
in water)
Reflection: bouncing back of light waves (ex.
Looking in a mirror)
LIGHT VOCABULARY
7. Transmission: some light is absorbed and some passes
through the object onto the other side.
8. Absorption: If the object looks white, it is because all
or nearly all of the radiation is reflected. If the object
appears to have any color other than white,
however, it means that all the visible radiation has
been absorbed except for the color you see. Objects
that absorb all the radiation striking them are known
as black bodies.
9. White light reflects light and is made up of 7 colors.
10. The color of an object is determined by the color of
light reflected by the object.