physical science: lesson ideas and activities presented by frank h. osborne, ph. d. © 2015 emse...
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Physical Science: Lesson Ideas and Activities
Presented byFrank H. Osborne, Ph. D.
© 2015
EMSE 3123Math and Science in Education
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ChemistryChemistry is the study of the structure and behavior of matter. Key
components include:• Structure and properties of matter• Chemical Reactions
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ChemistryK-2 Level Investigations
Structure and Properties of Matter
• 1. Sort objects according to the materials from which they are made or their physical properties, and give a rationale for sorting.
• 2. Use magnifiers to observe materials, then draw and describe what more can be seen using the tools.
• 3. Observe that water can be a liquid or a solid and can change from one form to the other.
Chemistry3-5 Level Investigations
Structure and Properties of Matter
• 1. Sort materials based on physical characteristics that can be seen by using magnification.
• 2. Observe that water can be a liquid or a solid and can change from one form to the other and the mass remains the same.
• 3. Recognize that water, as an example of matter, can exist as a solid, liquid or gas and can be transformed from one state to another by heating or cooling.
Chemistry3-5 Level Investigations
Structure and Properties of Matter– 4. Show that not all materials respond in the same
way when exposed to similar conditions.
Chemical Reactions– 1. Combine two or more materials and show that
the new material may have properties that are different from the original material.
ChemistryProperties of Matter
• Weight• Color• Texture• Hardness• Luster• Reflectiveness to light, sound and heat• Transparency to light• Make sound when struck, plucked or vibrated
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ChemistryStructure and Properties of Matter
• Air– Air takes up space
– Air can be poured
– Air can be compressed
– Air has weight
• Water has three states– Solid (ice)
– Liquid (water),
– Gas (steam)
ChemistryStructure and Properties of Matter
• Water has three states– Solid (ice)
• Ice has a density less than 1 so it floats on water
– Liquid (water)– Gas (steam, water vapor)
• Water vapor dissolves in air.
• This results in the humidity of the atmosphere.
Water expands when frozen
ChemistryStructure and Properties of Matter
Weight and Mass• Mass is the actual material in the object.• Weight is the effect of gravity on the mass.
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ChemistryStructure and Properties of Matter
Weight and Mass• A mass of 1 kg weighs 9.8 Newtons which is
approximately the same as 2.2 pounds.
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ChemistryStructure and Properties of Matter
Density• Density is the mass divided by the volume.• Water is defined as having a density of 1.• An object with density greater than 1 will sink
in water.• An object with density less than 1 will float on
water.
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ChemistryStructure and Properties of Matter
Physical Changes of Matter
• The form of the material changes but the same material is there at the beginning and at the end– Sawing wood– Crushing stone– Shaping clay– Bending metal
• Some changes involve heat– Adding heat melts ice– Removing heat freezes water
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ChemistryStructure and Properties of Matter
Melting Ice
• One can of water is frozen.
• Remove from the freezer and weigh.
• Allow all of the water to melt.
• Weigh it again.
• The weights are the same.
• When ice melts, the water changes state from solid to liquid but the amount of water does not change. 13
ChemistryStructure and Properties of Matter
Melting Ice• Two identical cans are filled with equal
amounts of water.• One can is frozen the other has a temperature
of 0°C.• The liquid warms up to room temperature.• The frozen water absorbs the same amount of
heat but the temperature does not increase.• There is heat of fusion. Heat is absorbed when
ice melts. Heat is given off when water freezes.14
ChemistryStructure and Properties of Matter
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ChemistryStructure and Properties of Matter
Melting Ice--graph shows change in temperature
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ChemistryStructure and Properties of Matter
Heating water• Add heat to water and the temperature of the water
increases
• The amount of heat needed to raise the temperature of a volume of 1 mL of water by the amount of 1°C is called a calorie.
• How many calories are needed to warm 100 mL of water from 10°C to 20°C?
Calculation• From 10°C to 20°C requires 10 cal per mL of water
• So, 100 mL X 10 cal per mL = 1000 cal17
ChemistryStructure and Properties of Matter
Gaseous water• Heating water above 100°C
produces steam. Steam must be confined in a contained enclosure such as a pipe or a pressure cooker.
• Water evaporates and dissolves in the air. This water is known as water vapor.
• Water vapor in the atmosphere is known as humidity.
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ChemistryStructure and Properties of Matter
Not all materials respond in the same way when exposed to similar conditions
• Drop a stone into water, it sinks. Drop a stick into water, it floats.
• Add heat to solid water, it melts. Add heat to solid iodine, it vaporizes.
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ChemistryStructure and Properties of Matter
Not all materials respond in the same way when exposed to similar conditions
• When liquid wax freezes, it shrinks. When liquid water freezes, it expands.
• When salt crystallizes from a solution, it sinks. When ice crystallizes, it floats
• Shake a bottle of water, nothing happens. Shake a bottle of soda and the carbon dioxide comes out of solution.
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ChemistryStructure and Properties of Matter
Not all materials respond in the same way when exposed to similar conditions
• Comparison of Pepsi and Diet Pepsi
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ChemistryStructure and Properties of Matter
Comparison of Pepsi and Diet Pepsi
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ChemistryStructure and Properties of Matter
• Comparison of Pepsi and Diet Pepsi
• Pepsi has 41 g of sugar. Diet Pepsi does not.
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ChemistryStructure and Properties of Matter
Separating Mixtures• Create mixtures of different materials and decide how
to separate them.
Questions:
• Suggest some materials that could be mixed together to illustrate this topic.
• What happens when the materials are mixed?
• What properties of the materials can be used to separate the mixture?
• Did you get one or both of the original materials back at the end?
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ChemistryStructure and Properties of Matter
Examples of Separating Mixtures• Salt and water form a solution
– Salt is recovered by evaporation of the water
• Sand and foam beads– Mixture is separated by density. Sand sinks in water, foam
floats.
• Mix flour and iron filings– The iron can be withdrawn from the flour using a magnet.
– Powdered sulfur can be used instead. The mixture can be separated with a magnet.
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ChemistryStructure and Properties of Matter
Sand and marbles are mixed in equal amounts
• The volume of the mixture is less than the two original volumes added together.
• Separate by passing through a screen which permits the sand to flow through but holds the marbles back.
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ChemistryStructure and Properties of Matter
Using magnifiers• Granite is a mixture of three minerals: mica,
feldspar and quartz. With the magnifier, quartz crystals look transparent, mica looks black and feldspar looks gray.
• The picture of the Lincoln Memorial on the back of a $5 bill has the names of states on it which can be seen with a magnifier.
• Salt under the magnifier looks like little cubes. Salt mineral has cubic crystals.
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ChemistryStructure and Properties of Matter
Separating sand and gravel particles
• Use a ruler, toothpick and a small pile of a mixture of sand and gravel. (Gravel is a mixture of granules and pebbles.)
• Separate the particles as best as possible into categories based on sizes using the Guide to Particle Sizes. It should be possible to distinguish between pebbles, granules and sand.
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ChemistryStructure and Properties of Matter
Guide to particle sizes
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ChemistryStructure and Properties of Matter
Separating liquids• Oil and water do not mix. Examples include:
– Salad dressing
– Oil and vinegar
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ChemistryStructure and Properties of Matter
Separating liquids• Immiscible liquids
are generally separated using a separatory funnel.
• At home, in the kitchen, we use a special separator cup.
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ChemistryStructure and Properties of Matter
Separating liquids• Cream floats on
milk• When the cream is
completely dispersed in the milk, the milk is said to be homogenized.
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ChemistryChemical Reactions
Chemical Reactions
• Chemical reactions produce new materials that are different from the original materials.
• Examples
– Rusting of an iron nail--the iron combines with oxygen to form iron oxide (rust) which is neither iron nor oxygen
– Mixing limestone with acid--the limestone releases carbon dioxide (gas) into the atmosphere while the rest of the rock becomes calcium oxide (lime) 33
ChemistryChemical Reactions
• Determining the amount of lime in limestone
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ChemistryChemical Reactions
Determining the amount of lime in limestone• Weigh out 20 g of limestone chips.• Place in 100 mL of vinegar.• Weigh out 20 g of limestone chips and place in
100 mL of water as a control.• Observe immediately and over a period of one
week. Shake occasionally.• Weigh two filter papers. Filter the solids from
each bottle through a filter paper. Dry. Weigh each paper with the dried solids.
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ChemistryChemical Reactions
Determining the amount of lime in limestone• Limestone decomposes in acid and releases
carbon dioxide. The remainder is CaO which can be weighed. The amount of CaO should be less than the original weight of limestone.
• The control should have no change.
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ChemistryChemical Reactions
Signs that a chemical reaction has taken place• Heat may be released. The system gets hotter.• Heat may be absorbed. The system gets
colder.• One or both reactants disappear while the
product begins to appear.• The product precipitates out of solution.• The state(s) of the reactants or products may
be different.37
Physics
Natural Laws as they apply to Motion,Forces, and Energy Transformations.
(Formerly Standard 9) 38
Physics Physics is the study of natural laws as they apply to motion, forces, and
energy transformations. Key components include:• Motion and forces• Energy transformations
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PhysicsK-2 Topics
• A. Motion and Forces– 1. Distinguish among the different ways objects
can move such as: fast and slow. in a straight line. in a circular path. back and forth.– 2. Show that the position and motion of an object
can be changed by pushing or pulling the object.
PhysicsK-2 Topics
• B. Energy Transformations– 1. Demonstrate that sound can be produced by
vibrating objects.
Physics3-4 Topics
• A. Motion and Forces– 1. Recognize that changes in the speed or direction
of a moving object are caused by force and that the greater the force, the greater the change in motion will be.
– 2. Recognize that some forces can act at a distance. gravity magnetism static electricity
Physics3-4 Topics
• B. Energy Transformations– 1. Identify sources of heat and demonstrate that
heat can be transferred from one object to another.– 2. Identify sources of light and demonstrate that
light can be reflected from some surfaces and pass through others.
– 3. Use devices that show electricity producing heat, light, sound, and magnetic effects.
– 4. Show that differences in sound (loud or soft, high or low) can be produced by varying the way objects vibrate.
PhysicsK-2 Examples
• Motion
• Invisible forces
• Energy
• Heat
• Light
• Sound
Physics3-4 Examples
• Simple machines
• Light and primary colors
• Electromagnetism
• Motion and forces
PhysicsMotion and Forces
Motion and Forces• A force is a push or a pull.• A force will make a resting object move or
will make a moving object move differently.• Force is related to the mass of the object and
its acceleration.• Position and motion can be changed by
pushing and pulling.
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PhysicsMotion and Forces
• A force is a push or a pull.• Gravity pulls the box down, the sidewalk
holds it up.
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PhysicsMotion and Forces
• Force is required to lift the box.
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PhysicsMotion and Forces
A force is a push or a pull.• Pull a block with the spring scale and read
the force.• Add a second block and repeat.• Add a third block and repeat.• Make a data table of the total weight of the
blocks and the forces required.• Plot the results on a graph and see what the
relationship is between weight and force.
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PhysicsMotion and Forces
A force is a push or a pull.
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PhysicsMotion and Forces
A force is a push or a pull.
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PhysicsMotion and Forces
A force is a push or a pull.• Less force is required using a ramp.• A ramp is a simple machine known as an
inclined plane.
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PhysicsMotion and Forces
A force is a push or a pull.Less force is required using a ramp.• Lift a block using a spring scale.• Record the force in Newtons.• Now, slide it up the ramp by pulling it with
the spring scale.• What force was required on the ramp?• How does the force on the ramp compare
with the vertical force?
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PhysicsMotion and Forces
A force is a push or a pull.• The block is suspended
from the spring scale.• The reading on the spring
scale is 2.4 N.
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PhysicsMotion and Forces
A force is a push or a pull.• Less force is required using a ramp.• The total vertical force was 2.4 N but when
the block was pulled up the ramp the force was only 1.0 N.
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PhysicsMotion and Forces
Rolling objects down a ramp• Which will roll faster, a solid ball, a hollow
ball, or a ring?
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PhysicsMotion and Forces
• Roll different objects down the ramp in pairs, as in a race
• Gravity makes the objects roll down the ramp
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PhysicsMotion and Forces
Moving air has lower pressureDemonstrations of the Bernoulli principle
• A ping-pong ball can be blown out of a paper
towel tube because of the air pressure. What
happens when you try it with a funnel?
• Blow air between two suspended balloons
using a paper towel tube? What do the
balloons do?58
PhysicsMotion and Forces
Pressure is the force per unit area (density X height). Spout C has the greatest pressure because it has the greatest height.
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PhysicsMotion and Forces
Some forces are invisible
• Gravity is an attractive force resulting from the mass of the Earth.
• Static Electricity can attract or repel depending on the charges of the objects.
• Magnetism is caused by electromagnetic force. It attracts or repels depending on polarity of the objects.
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PhysicsMotion and Forces
Static Electricity
• Static electricity results from electric charges.
• Opposite charges attract, like charges repel.
• Rubbing a comb with fur creates a static charge in the comb.
• The static charge attracts small bits of paper.
• Static charge can also be transferred to other objects such as suspended foam peanuts.
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PhysicsMotion and Forces
Static Electricity
• When the comb is rubbed with the fur, some of the electrons come off the fur and make the comb negatively charged.
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PhysicsMotion and Forces
Static Electricity
• The comb can transfer electrons to the foam peanuts.
• Try this and see what happens.
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PhysicsMotion and Forces
Magnetism
• Every magnet has a North Pole and a South Pole.
• Opposite poles attract, like poles repel.
• The North Pole of a Compass Needle points toward the North Magnetic Pole (which is of the South type).
• Some magnets have the North Pole highlighted in Red (watch out for this one with cheap toy-store magnets).
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PhysicsMotion and Forces
Demonstrations of magnetism
• Tape a small magnet to a toy car. Use a big magnet to push the car along without touching it.
• Use a small compass needle to demonstrate that electric wires have magnetic fields.
• Place a magnet under a sheet of paper and sprinkle the paper with iron filings.
• Use a magnet to determine which objects are magnetic and which are not.
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PhysicsMotion and Forces
Demonstrations of magnetism
• The magnetic field passes through the paper causing the iron filings to line up and visualize the magnetic field.
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PhysicsSound
Sound
• Objects make sounds when struck, plucked or vibrated.
• Examples– Carved wooden frog
– Guitar strings
– Bottles filled with different amounts of water
– Tahitian drum (To’ere)
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PhysicsSound
• Sound varies in pitch depending how the materials vibrate
• Sound travels as waves
• Waves are of two types– Longitudinal waves--slinky compression
– Transverse waves
• rope waves
• torsional wave model
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PhysicsWaves
Properties of waves
• Waves result from vibrations.
• There are two types: transverse and longitudinal.
PhysicsWaves
Transverse waves
• An up-and-down or side-to-side motion is propagated along the material.
Examples of transverse waves include:• Rope waves• Torsional wave model• Earthquake waves of the S (secondary or
shear) type• Ocean waves
PhysicsWaves
Longitudinal waves
• A compression is propagated along the length of the material
Examples include:
• Slinky compression
• Earthquake waves of the P (primary) type
PhysicsWaves
•Transverse (up and down) waves
•Longitudinal (compression) waves
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PhysicsWaves
Water waves are of the transverse type. The wind provides the energy for water waves. Size of the wave is determined by:
•Speed of the wind
•How long it blows
•How far the wind travels
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PhysicsWaves
Sound waves are the movement of air particles from the vibrations of an object. The particles bump into each other, creating vibration, which causes more particles to bump into one another.
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PhysicsWaves
There are two types of earthquake waves:
•S waves are shear stresses (moving back and forth) that travel as transverse waves.
•P waves are compressions that travel as longitudinal waves.•S waves are Slower then P waves.
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PhysicsWaves
Transverse waves
• An up-and-down or side-to-side motion is propagated along the material.
Examples of transverse waves include:• Rope waves• Torsional wave model• Earthquake waves of the S (secondary or
shear) type• Ocean waves
PhysicsWaves
Longitudinal waves
• A compression is propagated along the length of the material
Examples include:
• Slinky compression
• Earthquake waves of the P (primary) type
PhysicsWaves
Sound waves can be transmitted using the can and string “telephone”.
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PhysicsHeat
Heat
• Sources of heat– The Sun
– Combustion of fossil fuels
– Friction
– Conversion of electrical energy to heat energy
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PhysicsHeat
Heat can transfer from one object to another.• Conduction--direct transfer of heat by contact• Convection--heat is transferred by currents• Radiation--heat is transferred across space
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PhysicsLight
Light
• Sources of Light– The Sun
– Combustion
– Conversion of electrical energy to light energy
• Light transfers from one place to another by radiation.
• Light travels at its own speed.
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The End
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