6/30/03Prof. Lynn Cominsky1 Properties of Matter Part 1 NBSP Physical Science Leadership Institute...
49
6/30/03 Prof. Lynn Cominsky 1 Properties of Matter Part 1 NBSP Physical Science Leadership Institute Monday June 30, 2003
Transcript of 6/30/03Prof. Lynn Cominsky1 Properties of Matter Part 1 NBSP Physical Science Leadership Institute...
6/30/03 Prof. Lynn Cominsky 1
Properties of Matter
Part 1
NBSP Physical Science Leadership Institute
Monday June 30, 2003
6/30/03 Prof. Lynn Cominsky 2
Standard Connections
Properties of matter can be observed, measured and predicted (K)
As a basis for understanding this concept, students know that objects can be described…on the basis of physical properties such as WEIGHT
What are the common properties that scientists use to describe matter?
6/30/03 Prof. Lynn Cominsky 3
First Activity: Measuring matterHow do we measure mass?How do we know when 2 objects have the same mass?
Assemble a balance. Sketch it in your notes, and label the parts of the balance.
Experiment with the objects to see how the balance operates.
6/30/03 Prof. Lynn Cominsky 4
Equipment for first activity
Plastic balance
Pans
Set of random objects
Lots of washers
6/30/03 Prof. Lynn Cominsky 5
Further investigations:
Does it make a difference where the objects are placed in the pans?Does it make a difference if you switch the objects and place them in different pans?Does it make a difference if you use a different balance?What does it mean when we say something is in balance?
6/30/03 Prof. Lynn Cominsky 6
Operational DefinitionsAn operational definition describes the process that is used to make a measurementIt should be able to be used by another individual to repeat the measurement process using the same (or similar) equipment
6/30/03 Prof. Lynn Cominsky 7
Questions for the second activity:
How do we establish a set of standard masses?Can you write an operational definition for mass?
Equipment for the second activity:
Small pan balancesStandard mass sets
6/30/03 Prof. Lynn Cominsky 8
Mass activity #2Use nuts to measure the mass of an object in your setMeasure the mass of a single washer using the standard mass setMeasure the object using the standard mass set – did the results make sense?Use the standard mass set to measure a different objectPredict how many washers it would take to balance this object – did it work?
6/30/03 Prof. Lynn Cominsky 9
Thought experimentFirst weigh one object, and then weigh a second object.If you now put both objects on the scale at the same time, how will the total mass compare to the sum of your first two measurements?
6/30/03 Prof. Lynn Cominsky 10
Key concepts about massMass is a property of matter that can be measured using a standard set of objects. The typical standard that is used to measure mass is the gram.In most everyday situations, mass is conserved. M1 + M2 = M1+2
6/30/03 Prof. Lynn Cominsky 11
Vocabulary for ELLEqual-arm Balance: a physical instrument used to measure mass by comparing items Mass:property of matter that describes its quantityGram:standard unit of measurement for massStandard mass set: Set of masses which have a known relationship to one anotherWeight: result of gravity acting on mass
6/30/03 Prof. Lynn Cominsky 12
ELD ActivitiesCompare masses of different objects in the classroomMake a table to help remember new words:
Word Definition How I remember
6/30/03 Prof. Lynn Cominsky 13
Publisher’s Materials
Take some time to look through the state-adopted texts to find activities relating to measuring and observing objectsExamples: HC p. C5
6/30/03 Prof. Lynn Cominsky 14
Break – some things to think about
What is the difference between mass and weight?
How would your mass change if you lived on the Moon?
How would your weight change?
6/30/03 Prof. Lynn Cominsky 15
Standard ConnectionsStudents know that objects can be described…on the basis of physical properties such as SHAPE
How do we measure volume?How do we know when 2 objects have the same volume?How does measuring volume compare to measuring mass?
6/30/03 Prof. Lynn Cominsky 16
Third Activity – Volume of a Solid Given: a large block and lots of smaller cubesUse the cubes to make a model of the large blockCount the number of cubes that it takes to make your modelRepeat for several different objectsIs volume always = length x width x height?
6/30/03 Prof. Lynn Cominsky 17
Fourth activity: Volume and Liquid
How do we measure the volume using a liquid?What is the relationship between 1 cm3 and 1 mL?
Graduated cylindersWaterPlastic cubes and other objects
Equipment for Fourth activity
6/30/03 Prof. Lynn Cominsky 18
Fourth activity: Volume and Liquid
Fill the graduated cylinder to the 35 mL mark. Drop in 7 of the plastic cubes. Measure each cube with a ruler.How much does the water level rise?How could you put marks on the side of the cylinder if they were not already there?Write an operational definition for volume
6/30/03 Prof. Lynn Cominsky 19
More questions about volume and mass:
How would you measure the volume of an irregularly shaped object if it was too large to fit into a graduated cylinder?Does each gram of a submerged object displace a gram of water?Could we measure the mass of a submerged object by the water displacement method?
6/30/03 Prof. Lynn Cominsky 20
Thought experimentSuppose a graduated cylinder is filled up to the 50 mL mark with dry sand. Then suppose that 30 mL of water is poured into the cylinder. Will the final volume of the water and sand be measured at 80 mL? Explain your reasoning.
6/30/03 Prof. Lynn Cominsky 21
Key concepts
Volume – is measured using a standard set of objects such as uniform cubes, or by measuring a liquid such as water, which is displaced by the object to be measuredVolume is NOT conserved: V1 + V2 is not necessarily equal to V1+2
6/30/03 Prof. Lynn Cominsky 22
Volume: the amount of space that an object displacesGraduated Cylinder: A physical instrument used to measure volume of liquids (directly) or of solids (by submersion)
Vocabulary for ELL
6/30/03 Prof. Lynn Cominsky 23
ELD Activities
There are at least two volumes associated with a tin can.What are they are and how would you measure each?
6/30/03 Prof. Lynn Cominsky 24
Publisher’s Materials
Take some time to look through the state-adopted texts to find activities relating to measuring volume that could be used in your classroom.
6/30/03 Prof. Lynn Cominsky 25
Lunch break - Things to think about
Consider the two boxes shown. Their dimensions are given in meters. Answer the following questions about the boxes. Explain your reasoning.
36
22
3
3
Box A Box B
6/30/03 Prof. Lynn Cominsky 26
Lunch break questions:Suppose these boxes, including their lids, are made of very thin plywood. Which box requires more wood?Which box will hold more peanuts?Which box is heavier (empty)?Which box would say is bigger and why?
6/30/03 Prof. Lynn Cominsky 27
Standard ConnectionsStudents know that objects can be described…on the basis of physical properties such as FLOATING & SINKING
How do we measure density?How can we tell if an object will sink or float?
6/30/03 Prof. Lynn Cominsky 28
Key concepts: density
Density is defined as the mass of an object divided by its volumeDensity is a characteristic property of an object: under the same conditions, all objects made of the same material have the same densityThe units for density are g/cm3 – The value tells you how many grams are in one cubic centimeter of material
6/30/03 Prof. Lynn Cominsky 29
Thought experiment: Density
A block of wood has a mass of 18 g and a volume of 25 cm3
How would you interpret the number 18/25?How would you interpret the number 25/18?Write an operational definition for density
6/30/03 Prof. Lynn Cominsky 30
Fifth Activity: Sinking and Floating
Given: a set of objects, and a beaker of water. Water’s density is 1 g/cm3
Predict whether your objects will sink or float, then test out your predictionsCan you turn any sinkers into floaters? Floaters into sinkers?Separate the sinkers and floaters into separate groups
6/30/03 Prof. Lynn Cominsky 31
Fifth Activity: Sinking and Floating
What similarities are there among the objects that floated? What differences?What similarities are there among the objects that sank? What differences?Make a list of things that you believe influence whether or not an object can floatHow will you test your ideas about sinking and floating?
6/30/03 Prof. Lynn Cominsky 32
Sixth activity: Why does a boat float?
Tear off two pieces of aluminum foil that are approximately the same sizeMake one into a boat Crumple the second one up into a ballMeasure the mass of each pieceDrop each into the pan of waterWhat happens?
6/30/03 Prof. Lynn Cominsky 33
Sixth activity: Why does a boat float?
Can you determine the density of each piece? Why or why not?Predict how many washers you can add to the boat before it will sink.Test out your prediction.Does the mass effect whether an object sinks or floats?Does the volume?
6/30/03 Prof. Lynn Cominsky 34
Key concepts: Sinking and Floating
When an object is totally submerged in a liquid, it displaces a volume of the liquid equal to its volumeIf the object is floating in a liquid, it displaces a volume of the liquid which has the same mass as the entire objectIf you know the density of both the object and the liquid, you can calculate how much of the object is submerged in the liquid
6/30/03 Prof. Lynn Cominsky 35
Math connectionsAn ice cube with volume of 1 cm3 has a density of 0.9 g/cm3
It is floating in very salty water that has a density of 1.2 g/cm3
What is the mass of the ice cube?What is the mass of the salty water that it displaces?What is the volume of the water that it displaces?How much of the ice cube floats above the water?
6/30/03 Prof. Lynn Cominsky 36
Vocabulary for ELLSinking: when an object is entirely covered with liquid
Floating: when only part of the object is covered with liquid
6/30/03 Prof. Lynn Cominsky 37
ELD Connections
When someone is slow to understand, they may be called dense. Why?When someone is feeling sad, they are said to have a sinking feeling. Why?When someone is feeling happy, they are said to be floating on air. Why?
6/30/03 Prof. Lynn Cominsky 38
Publisher’s Materials
Take some time to look through the state-adopted texts to find activities relating to sinking and floating that could be used in your classroom.Examples: HM p. 198, HM p. C7
6/30/03 Prof. Lynn Cominsky 39
Break – things to think about
You are sitting in a boat which is floating in a small pond. Next to you, inside the boat, is a large rock. The density of this rock is 10 g/cm3. You pick up the rock and throw it over the side of the boat. Does the water level in the pond go up, stay the same or go down? Explain your answer.
6/30/03 Prof. Lynn Cominsky 40
Standard ConnectionsStudents know that objects can be described…on the basis of physical properties such as ATTRACTION TO MAGNETS
What types of materials are attracted to magnets?How can we tell the difference between a magnet and a metal?Are any materials repelled from magnets?
6/30/03 Prof. Lynn Cominsky 41
Equipment for third activityMagnets of various sizes and shapesSome pieces of non-magnetized metalOther things like rubber, wood, glass, plastic, aluminum, paper clips, etc.
Seventh activity: Exploring magnets
Use different magnets and bag of objects to explore magnetic properties
6/30/03 Prof. Lynn Cominsky 42
A few things to try:
Bring pairs of like and unlike magnets together at different locationsPlay with magnets and pieces of metal like paper clipsPlay with magnets and other materialsWhat common properties do objects have that are attracted to magnets?Some things on your own!
6/30/03 Prof. Lynn Cominsky 43
Key conceptsMetals are always attracted to magnetsMagnets are both attracted and repelled from other magnetsSome metals are more strongly magnetic than others – iron is typically used for magnetsSome parts of the magnet are more magnetic than others
6/30/03 Prof. Lynn Cominsky 44
Vocabulary for ELL Magnet: material that can both attract and Magnet: material that can both attract and
repel other magnets. Iron is most common.repel other magnets. Iron is most common. Pole: Part of the magnet where the force is Pole: Part of the magnet where the force is
the strongestthe strongest Metal: material that is often attracted to Metal: material that is often attracted to
magnets and a good electrical conductormagnets and a good electrical conductor Horseshoe magnet: Horseshoe magnet:
U-shaped magnetU-shaped magnet
NS
6/30/03 Prof. Lynn Cominsky 45
Publisher’s Materials
Take some time to look through the state-adopted texts to find activities relating to magnets that could be used in your classroom.Examples:
6/30/03 Prof. Lynn Cominsky 46
ELD Activities
Make a list of things that are attracted to magnetsMake a list of things that have magnets in themWhy do we say that some people have magnetic personalities?
6/30/03 Prof. Lynn Cominsky 47
Take away – brain teaser
Someone gives you 2 bars of identical shape, weight and appearance One is a magnet and the other one is metalHow can you tell which is which? (You can’t use any other equipment, you can’t touch the bars to anything but each other and you don’t know which way North is located.)
6/30/03 Prof. Lynn Cominsky 48
Lesson Study Activities
Identify a key concept from today’s lecture for further developmentReview the publisher’s materials about this key concept Discuss the best way to present this key concept in your classroom
6/30/03 Prof. Lynn Cominsky 49
Resources
Physics by Inquiry – L. McDermott and the PEG at U Washington
