Ch 5 ppt - Effingham County Schools

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Lesson 1
Essential Question:
What are physical changes in matter?
Physical Change: A change in the size, shape,
or state of matter that doesn’t change it into a
new state of matter
Examples:
melted juice bar/melting snowman
broken glass
cut paper
Energy: the ability to cause change
Where did the energy come from?
1) Ball breaking a window? moving ball
2) Paper being cut? muscles in hand
3) Water evaporating? sun
Let’s create some physical change by
making a paper snowflake!
New entry in Science IN: Compare and contrast the paper
square and the snowflake. Be sure to use the word physical
change.
Making Paper Snowflakes
The paper square and the snowflake are similar
because………………. They are different because……………
My snowflake design is ………….
Lesson 2
Essential Question:
What happens to matter when it is
heated or cooled?
Heating and cooling matter changes the way its particles
move and the amount of space between the particles.
Thermal energy: total energy of the particles of matter
Thermal energy can be added and taken away from matter.
You can’t see thermal energy, but you can feel it as heat.
Heat: the flow of thermal energy from a warmer to a cooler
area
Adding and taking away thermal energy
(solid)
+ thermal energy = melted butter
(liquid)
melted butter - thermal energy =
(liquid)
(put on ice pack)
(return to solid)
When you heat matter, its thermal energy grows.
The particles of matter move faster and farther
apart. When you cool matter, you take away
thermal energy. The particles of matter slow
down an move close together.
Temperature: A measure of how hot or cold
matter is
 Particles of matter move slower in the cold
and faster in the warm.
 Tool of measurement: thermometer
 Measure in units called degrees: Celsius &
Fahrenheit
Matter stays the same:
 Matter may look different after a physical
change, but the matter does not change. Its
particles are just packed together differently.
 After a physical change, the matter’s physical
properties such as color and density, stay the
same. Its mass also stays the same.
Iron –
• When iron gets heated, it gets soft.
• Soft metals can be hammered and bent into
different shapes. It can get so hot it
becomes a liquid.
Lesson 3
Essential Question:
What are mixtures and solutions?
Enter these into your Chapter 5 Table of Contents:
Lesson 3 Notes
(1 page)
Mixtures vs Solutions
(2 pages)
Mixture: matter made of 2 or more substances
or materials that are physically combined
Examples:
1. bubbles
2. coin jar
3. trail mix
How can you separate mixtures?
• by hand
• change in state
• density differences
*You cannot separate all mixtures by hand. Some
mixtures can be separated using a change in state.
Example: sugar & water ~ boil the water
*Separate by density
Example: soil mixed with water
Solution: A mixture where the particles of one kind of
matter are mixed evenly with the particles of other
kinds of matter
Dissolve: to mix completely with another substance to
form a solution
*Solubility – the measure of how much a substance
can dissolve into another substance.
Sand not soluble
Salt
more soluble
Sugar very soluble
Mixture
marbles + water
parts can be easily
seen & removed
Solution
salt + water
All solutions are mixtures,
but solutions are evenly
mixed. One substance
dissolves in the other.
Examples:
Example:
Sand
&
water
Particles are
mixed
together, not
necessarily
even.
can by
easily
separated
Mixture
made up of
2 or more
types of
matter mixed
together
Both
are
mixtures.
air
salt water
sugar water
Solution
Particles
are evenly
mixed.
not easily
separated;
a substance
dissolves
Lesson 4
Essential Question:
What are chemical changes in matter?
Chemical change: a change in matter that makes new
kinds of matter with different properties
Chemical changes need energy. Energy is given off or
taken in during a chemical change.
During a chemical change, molecules break apart and
mix with different ways with other atoms and molecules.
This forms new matter with different properties.
The atoms and molecules mix in new ways during a
chemical reaction: a chemical change
The matter you start with: reactant
The product is the NEW matter that is formed.
Proof that chemical change is happening:
1) bubbles
2) change in color, state, temperature
3) change in smell, energy
4) a new product is formed
How chemical changes take place:
Atoms and molecules are held together by chemical
bonds. During a chemical reaction, the bonds are
broken.
New bonds form between different atoms and
molecules. This causes new matter, or products, to
form.
The new products are made up of different atoms and
molecules, so they have different properties from the
reactants.
EXAMPLES OF CHEMICAL CHANGES
•
CARS BURN GAS
•
BURNING WOOD
•
RUSTING METAL
•
FIREWORKS
EXPLODING
•
TOASTED
MARSHMALLOW
•
BAKING A CAKE
•
FOOD INTO
ENERGY FOR
YOUR BODY
•
APPLE EXPOSED
TO AIR
•
HYDROGEN
PEROXIDE (ON A
CUT)
~ LAVA LAMP ~
Creating Chemical Change
1. Pour water into the plastic bottle until it is around one
quarter full.
2. Pour in vegetable oil until the bottle is near full.
3. Wait until the oil and water have separated.
4. Add around a dozen drops of food coloring to the bottle
(choose any color you like).
5. Watch as the food coloring falls through the oil and mixes
with the water.
6. Cut an Alka-Seltzer tablet into smaller pieces (around 5 or 6)
and drop one of them into the bottle. Things should start
getting a little crazy!
7. When bubbling stops, add another piece of Alka-Seltzer and
enjoy the show!
Lava Lamp Experiment
Our lava lamp………………….
• What supplies did you
need?
• Describe the process in
making the lava lamp.
(You should use the
word chemical change.)
• What did the lava lamp
look like?
The reactants are……………
The product is ……………
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