P3
Properties, Particles, Patterns
LeaPS Summer Workshop
July 2011
Rowan Co Middle School
8th grade Activities
Elizabeth Roland
and
Diane Johnson
1
Topics to be covered:
Atomic Structure
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Matter is made of atoms
Atoms composed of small parts
Measurable properties
o Mass
o Electrical charge
Protons, neutrons, electrons and their location
Electronic force holds atoms together
o Attraction, nucleus and electrons
Size
o Too small to be seen with microscope
Basic structure
o Nucleus
o Electron cloud
Scale
Periodic Table
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Classify substances by how they react in different situations
Periodic law
Organized by increasing number of protons, then repeating patterns
of physical (e.g. density, boiling point, and solubility) and chemical
(flammability and reactivity)
Groups of elements with similar properties
o Metals, highly reactive, less reactive,
o Non-metals – highly and less reactive
o Non-reactive
Element
o Single type of atom
o Atoms of an element are alike but different from atoms of
another element
o Do not break down during chemical reactions
Biogeochemical
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Physical and chemical changes
Conservation of matter and energy
Movement of elements between organisms physical environment
to/in the Earth’s systems (repeated over long period of time)
Factors that influence movement of elements among solid earth,
oceans, atmospheres and organisms
Describe interactions that cause the movement
2
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Earth is a system containing a fixed amount of each element which can
exist in several reservoirs
Conservation of Matter/Energy
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Idea of atoms explains conservation of matter
Atoms present today have always existed
Investigate the seemingly indestructible nature of atoms and concept
of conservation of matter
Total amount of matter remain constant even though form and
location change
Energy can be transferred in many ways but neither created nor
destroyed
Infer where energy goes
Explain law of conservation of energy
Connect energy transformation to life
Modeling
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Analyze and interpret models and representations of:
o basic atomic structure
o elements – single type of atoms
Because not directly observable:
o physical and conceptual models to enhance understanding
o purpose determines type of model to use
3
Relevant Kentucky Program of Studies and Core Content
Statements for Eighth Grade
Understandings
SC-8-STM-U-1
Students will understand that all matter
is made of tiny moving particles called
atoms, which are far too small to see
directly through a microscope. The
atoms of any element are alike but are
different from atoms of other elements.
Skills, Concepts
SC-8-STM-S-1
Students will classify
substances by how they
react in given situations
CCA
SC-08-1.1.1
Students will:
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interpret models/representations of
elements;
classify elements based upon patterns in
their physical (e.g., density, boiling point,
solubility) and chemical (e.g., flammability,
reactivity) properties.
Models enhance understanding that an element
is composed of a single type of atom.
Organization/interpretation of data illustrates that
when elements are listed according to the
number of protons, repeating patterns of physical
(e.g., density, boiling point, solubility) and
chemical properties (e.g., flammability,
reactivity), can be used to identify families of
elements with similar properties.
SC-08-1.1.2
Students will understand that matter is made of
minute particles called atoms, and atoms are
composed of even smaller components. The
components of an atom have measurable
properties such as mass and electrical charge.
Each atom has a positively charged nucleus
surrounded by negatively charged electrons. The
electric force between the nucleus and the
electrons holds the atom together.
SC-8-STM-U-2
Students will understand that because
atomic structure is not directly
observable, models (physical and
conceptual) are used to facilitate
understanding. What kind of model to
use and how complex it should be
depends on its purpose.
SC-8-STM-S-2
Students will analyze
models/representations of
elements and basic
atomic structure
SC-8-STM-U-3
Students will understand that elements
do not break down during chemical
reactions (e.g., heating, exposure to
electric currents, reaction with acids).
SC-8-STM-S-3
Students will describe
and illustrate the
movement of elements
between organisms and
their physical
environment and within
the Earth system
SC-08-1.1.3
Students will understand that the atom’s nucleus
is composed of protons and neutrons that are
much more massive than electrons.
SC-8-STM-U-4
Students will understand that the idea of
atoms explains the conservation of
matter: If the number of atoms stays the
same no matter how they are
rearranged, then their total mass stays
the same. The atoms that are present
today are the same atoms that have
always existed.
SC-8-STM-S-4
Students will analyze
factors that may influence
the movement of
elements among the solid
Earth, oceans,
atmosphere and
organisms
SC-08-1.1.4
Students will describe interactions which cause
the movement of each element among the solid
Earth, oceans, atmosphere and organisms
(biogeochemical cycles)
SC-8-STM-U-5
Students will understand that there are
groups of elements that have similar
properties, including highly reactive
metals, less-reactive metals, highly
reactive nonmetals (such as chlorine,
fluorine and oxygen) and some almost
completely non-reactive gases (such as
helium and neon). Some elements don’t
fit into any of the categories; among
them are carbon and hydrogen,
essential elements of living matter.
SC-8-STM-S-5
Students will investigate
the relationship between
the seemingly
indestructible nature of
the atom and the concept
of conservation of matter
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Earth is a system containing essentially a fixed
amount of each stable chemical atom or element
that can exist in several different reservoirs. The
interactions within the earth system cause the
movement of each element among reservoirs in
the solid Earth, oceans, atmosphere and
organisms as part of biogeochemical cycles.
SC-8-STM-U-6
Students will understand that over a
long time, matter is transferred from one
organism to another repeatedly and
between organisms and their physical
environment. As in all material systems,
the total amount of matter remains
constant, even though its form and
location change.
SC-8-ET-U-1
Students will understand that energy
can be transferred in many ways, but it
can neither be created nor destroyed.
SC-8-ET-S-1
Students will explain the
law of conservation of
energy and infer where
energy goes in a number
of real-life energy
transformations
SC-08-4.6.2
Students will:
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describe or explain energy transfer and
energy conservation;
evaluate alternative solutions to energy
problems.
Energy can be transferred in many ways, but it
can neither be created nor destroyed.
SC-8-ET-S-2
Students will identify the
energy transformations
that occur in the
‘production’, transmission
and use of energy by
people in everyday life
(e.g., electric power,
automotive fuels, food)
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Learning Targets
Atomic Structure
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I can identify the parts of an atom which made up its structure.
(nucleus, electron cloud, neutron, electron, proton)
I can distinguish the parts of an atom based upon mass and charge.
(proton, electron, neutron)
I can demonstrate, in words and pictures, how the size of an atom
compares to a visible object.
I know what holds an atom together.
Periodic Table
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I can define an element. (single type of atom)
I can classify atoms into element categories.
I can classify substances using reactivities into like groups (families).
I can describe patterns from periods and families from the periodic
table.
I can predict missing elements based upon existing pattern.
I can identify chemical trends using atomic numbers and data in
tables/graphs (flammability, and reactivity).
I can identify physical trends using atomic numbers and data in
tables/graphs (density, boiling point, and solubility).
I can identify groups of elements with similar properties (metals, nonmetals and non-reactive).
I can use reactivities to classify substances into like reactivity groups.
I can rank order reactivity based upon data patterns.
Biogeochemical
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I can compare the elements essential for life to those found in the Earth’s
crust, oceans, and atmosphere.
I can make inferences about the source of these elements.
I can identify processes that produce and consume organic forms of
carbon molecules and CO2 molecules.
I can explain how a plant uses CO2.
I can explain a plant’s role in carbon cycling.
I can describe how matter and energy are transformed in a food chain and
ecosystems.
I can describe how matter and energy are transformed during
decomposition.
I can describe interactions between the bio- and atmosphere in terms of
carbon cycling.
I can describe how different types of plants store Carbon.
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I can explain how land use decisions can cause imbalance in the amount of
Carbon released or stored.
I can describe how different types of soils store Carbon.
I can explain how different variables affect decomposition by soil
organisms.
Conservation of Matter
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I can modify the definition of matter (to include the concepts of atom
and element).
I can explain the relationship between atoms and the conservation of
matter.
I can use the existence of atoms to demonstrate the conservation of
matter.
I can interpret evidence which supports the conservation of matter.
Modeling
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I can explain how models are predictive.
I can use a model to explain the effect of increasing and decreasing
scale (in 2-D and 3-D).
I can explain how models are different from reality.
I can distinguish between different forms of models.
I can analyze multiple, basic atomic structure models for advantages
and limitations.
I can identify the form of model to use.
I can explain that the type of model you use is based upon the model’s
purpose.
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Models,
Atoms and
Atomic
Structure
1. An Introduction to Models and Modeling
Models and Modeling is the topic for this series of experiences and it will be cycled
back to multiple times in the unit. Development of a fundamental comprehension of
models and modeling is needed as students are beginning to learn about various
atomic models, molecular models, and reaction mechanisms. In this first sequence
of experiences, students will practice development and refinement of a model.
Model refinement requires using evidence and asking new questions of a situation.
Learning Targets:
I can explain how models are predictive.
Focus Question:
What is a scientific model?
Key Vocabulary:
Modeling, Model
Sequence of Experiences
(1)Is it a model? And discussion
15 min
(2)Water expander demonstration and discussion
10 min
(3)Development of water expander original models in
small groups
20 min
10 min
(4)Sharing of Models to Class with Discussion
(5)Testing Box Again
5 min
(6)Revision of Model
10 min
(7)Discussion and Introduction of the Black “X” Box
10 min
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1. Opening Act
Materials Needed:
Copy for each student of the probe: Is It a Model? From Uncovering Student
Ideas in Science Volume 4
Water Expander Box:
Wooden box large enough to hold a 1 gallon bucket (type used to
wash car with) or a cardboard box
A plastic 1 gallon bucket
Plastic tubing
Two funnels (1 enters directly into the bucket from the top, the other
comes out the side and is attached to the plastic tubing)
Water
Foam Sealant or Silicon
Large chart paper to draw ideas or a roll of paper on a stand
Paper towels
2, 500mL beakers
1 extra bucket (for water catching)
Crayons
Black cardboard with large question mark
(1) ‘Is It a Model?’ Probe
Explain to the students the format of the probe. The students need to
mark with an “X” what is a model and leave the space blank if they do not
think it is a model. At the bottom, students need to explain their
reasoning in relationship to what they have marked. When students have
completed the model probe, ask them to find a partner. Discuss with
partner what each student has selected and the reason for selection. Ask
students to come to an agreement about their selected items and a reason.
Teachers should ask students to share their reasoning and tally how
many students selected each item. Keep this information for discussion
later in the unit for potential refinement. Have students to staple their
probe into their science notebook for safekeeping and to refer to later.
Spend time developing a whole class definition for the term model. Take
no more than 10 minutes.
(2) Water expander demonstration and discussion
Teacher should direct student’s attention to a box in the room. Ask
students to make some observations about the box. Record these
observations on the board (sometimes it helps to have a student
volunteer to write observations on the board for you while you direct
traffic). Next, ask students to make predictions about what the box does.
Finally, ask students to suggest a test for the box. (To prompt the
direction of the conversation, I often have a 500ml beaker of water
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already out near the box). Take the suggestion to pour water into the box
and ask for predictions. Prepare the test with two volunteers for the
water test. (Make sure you have extra beakers or buckets to catch all the
water). Have one student pour in the water and the other student hold a
like-sized beaker at the other end. As water begins to pour out and starts
to over flow the beaker, pass them another beaker, and then a bucket.
Ask students to share their observations of the demonstration.
(3) Development of Water Expander Original Models
In groups, students will draw what they think is inside the box which
allows for more water to come out of the box then poured into the box.
Student groups will have one large piece of paper and a box of crayons.
Allow time for students to discuss and draw. Encourage students to label
the parts of the model and then describe how it works at the bottom of
the drawing. Forewarn students they will share their models with the
class.
(4) Sharing Water Expander Models with Class
Allow each group to stand in one section of the room in a circle (if
possible). Each group will hold up their model and explain. Give time for
groups to comment on other’s models. Then return to tables. Ask each
group what they predict would happen to their model if another 500mL
of water was added.
(5) Testing of the box
Ask for a volunteer to pour an additional 500ml of water into the box.
(6) Revision of Models
Explain that based upon the results of the test, students should revise
their proposed model. Allow time for students to work on revisions (a
second drawing on the back with their reasons for revision). As a teacher,
you may elect to have students share their revisions to the model and
reasons for revision to the whole class or to simply turn this in to you.
(7) Discussion and introduction of the black “X”
Ask students: Is the water expander a model and why? No, because it is
the real thing.
Ask students: Are your drawings a model and why? Yes, because it is a
representation of what is inside the water expander.
Ask students: How do your drawings relate to your definition of a model?
Answers will vary.
Ask students: Do we need to adjust our definition of a model? How would
you like to adjust our definition? Answers will vary.
Ask students: What is the purpose of a model? Share ideas or predictions
about something. How do scientists use models? To clarify thinking and
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to communicate with one another (there are other reasons, but these are
the two main ideas we need).
Ask students: Why did you refine your model? Answers will vary
Ask students: Should a model have the power to predict? Yes, otherwise
the model needs to be refined.
Now hold up the black 2-D box with a question mark (you may wish to attach it
to the wall for the rest of the atomic structure portion of the unit). Ask students
what do they think the black question mark box represents? Then explain that
we will be exploring atoms and atoms internal structure. As an exit slip for the
day, you may ask the students to write down all that they know about atoms and
what they would like to know about atoms.
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2. Observe It with What?
Today students will practice making observations using their five sense and
two tools: a magnet and balance. We are still working within models but
including classification and making inferences. This will lead into how the
internal atomic structure was determined by making observations from
many experiments which led to inferences about internal structure. Students
will continue to make observations, but they will discuss how their
observations and classification schemes in relationship to how they are
limited by the containers. Then students will discuss how this may have
influenced experiments and the development of a model for the internal
structure of an atom.
Learning Target:
I can explain how models are predictive.
Focus Question:
How do scientists study what they cannot see?
Key Vocabulary:
Inference, Infer
Sequence of Experiences
(1) Students will make observations of objects that
are not hidden
10 min
(2) Classification based upon properties (open sort)
and whole class discussion
10 min
(3) Students will make observations of objects that
are ‘hidden’
10 min
(4) Classification based on properties, and whole
class discussion
15 min
Materials:
Magnets (1 per group)
Balances
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Sets of Objects for group observations in brown lunch bags: sugar in clear
plastic vial, cotton ball, large wooden block, oatmeal, washer, rice (in clear
plastic vial), rock
Create a set of observation containers:
About 40 small boxes, or film canisters (or any plastic opaque
container), taped shut to avoid peaking during the day
Tape
With nail polish, silver sharpie or other instrument to label each
container with a number
Use the following table to fill the canisters with materials.
Container
Items Added
Number
1
A handful of oatmeal or half filled with oatmeal
2
A marble
3
Two pennies (or washer)
4
A marble and a penny (or washer)
5
One penny (or washer) and a layer of oatmeal
6
Water (if in film canister)
7
Water and one marble (if in film canister)
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Half rice and half oatmeal
9
All rice
10
Small magnet
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Three or Four Paper Clips
12
Small magnet with oatmeal
13
Three or Four Rocks
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Wood Chips
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Cotton Balls
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Oatmeal in the bottom with cotton balls on top
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Plastic beads
18
Sunflower seeds
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All Sand
20
Sand and a penny (or washer)
(1)
Students will make observations of objects that are not hidden
Teachers should have bags of materials for each group. Explain that the
students are to make careful observations of each item in the bag. Give them
a time limit. If you have the ability, project a timer.
(2)
Classification based upon properties (open sort) and whole class
discussion
When time is up, ask groups to classify all the items using one property.
Have each group move the items into a set. Next, have students in groups,
switch to another group and predict what is the classification scheme used.
Write down their prediction and then pass it to the group that created the
scheme. If they are correct, the group needs to return to their desks. When
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all groups have returned to their desks, create a t-chart on the board. (Have
one member of each group place all items in a bag and return to a specified
location in the room.) Record on the left the rule used to sort and on the
right side the specific property used to classify the objects. For example: if
the rule was it is white, the property used would be color.
(3)
Students will make observations of objects that are ‘hidden’
For this activity, the teacher needs to have at least two sets of 20 containers.
Explain that students need to make observations in their groups of all 20
containers. Ask students questions such as what can you do to make an
observation? If they do not suggest mass, reword the question to include
what types of tools could one use to make observations. Have magnets out.
Allow time for observations (you may need to prompt groups to use balances
and to return containers they have completed observing).
(4)
Classification based on properties, and whole class discussion
When all groups have completed their observations, explain that they need to
sort their containers into 2 groups using an observed property. Explain that
they will use numbers instead of the containers because there are only two
full sets in the room. When all groups have completed this task, ask each
group to share what property/rule they have used to sort the containers.
Create a new t-chart with rules and properties. Ask students to record the tchart in their science notebook. Have students write down what differences
they see in the types of properties used to classify in part 1 compared to part
2. Have them provide reasons for the difference.
Questions to consider from the data:
How does the bag/box/film canister change the types of observations made?
How does the information available change from task to task?
Does this influence the data and in what way or ways do/does it influence the
data?
Can you always see everything?
What are some things you cannot see but know they exist?
If you cannot see it does it still exist?
What can you do to “prove” to someone that an object is in an unopened and
unopenable box?
Notebook:
Have students reflect upon the first two model activities in their notebook.
Use the following frame for responses:
In the first activity with models we __________________________________________. In
the second activity with models we __________________________________________. The
similarity(ies) between the two activities were _____________________________. The
difference (s) between the two activities were ______________________________.
Both activities are about models because ___________________________________.
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Finally, have students review their ‘Is It a Model?’ probe, which they stapled
into their science notebook to make adjustments as needed.
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Atoms and Structure
Models,
Atoms and
Atomic
Structure
2. Size and Scale Activity Part 1
Learning Target:
I can use a model to explain the effect of increasing and decreasing
scale (in 2-D and 3-D).
Focus Question:
What is the effect of scale on 2-D materials?
What is the effect of scale on 3-D materials?
Key Vocabulary:
Scale, Powers of Ten
Sequence of Experiences
2 min
(1) How Small is Small? How Large is Large?
(2) 2-D scaling and discussion
20 min
(3) 3-D scaling and discussion
20 min
(4) Graphing and approaching zero not reaching zero,
whole class
8 min
Materials:
Graphical Analysis or Excel
Graphing paper-the green with the little tiny squares
Clay
Rulers (available for students to use)
Balances (available for students to use)
(1) How Small is Small? How Large is Large?
What is the smallest thing you can see? Answers will vary.
What is the smallest thing you can and have seen with a microscope? Answer
will vary
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(2) 2-D scaling and discussion
In this activity students should work in small groups. Each group member
will be responsible for writing out an explanation for how to scale the paper
either up or down ‘one step or two steps.’
Start with a metric ruler that has centimeters marked. Explain that for small
objects such as shoe length, diameter of a softball, or depth of a juice glass
can be easily measured using centimeters. But what about measuring
something a little smaller? For example, what would you use to measure the
length of an eyelash, or the thickness of a bee’s wing? You would want a finer
measurement. That would be a millimeter and it is one power of ten smaller
then a centimeter. Or that means it takes 10mm to equal 1cm. If you look
very carefully at a metric ruler, how many lines do you see between the 1cm
and the 2cm line? Nine lines. The ruler is in a straight line and it is only
measuring 1-D. If you use the ruler to measure in two directions, you are
measuring in 2-d (for example on graph paper, the horizontal and vertical
lines).
Today, your groups are going to start with an 8 ½” by 11” sheet of paper.
Your group needs to determine how to model increasing the paper by one
power of ten, and by two powers of ten. Then you need to develop a
procedure to model decreasing it by 1 power of ten and then by 2 powers of
ten. Each group member is responsible for writing the description for one of
the four conditions. Also, provide illustrations for increasing and decreasing.
Start the discussion by asking one group to describe how they increased their
paper by 1 power of ten.
When you increased the paper by 1 power of 10, what happened to the
amount of surface area? Answers will vary. But in general, each piece of
paper will need nine more pieces of paper.
Could you contain that many papers in the classroom? yes
What about when you increased it by 2 powers of 10? You would do the
same thing, but each of the 10 papers will need 9 additional papers. So that
would be 100 papers. What happened to the size and could it be contained in
the classroom? It could not be laid out flat, but if stacked it would fit. Where
could you have all the papers spread out for two powers of 10? The gym,
outside, the hallway, etc.
Ask for a student to describe how they scaled the paper down one power of
ten. Ask if anyone has anything they would like to add or modify to the
response? They would make nine even cuts in the horizontal direction and
nine even cuts in the vertical direction.
Ask students: Do you think is it possible to have powers of ten using volume?
Why or why not? Answers will vary.
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(3) 3-D scaling and discussion
Now in the same groups, give each group a baggie containing a lump of clay
(about ¼ of a stick). Explain that each group will again assign members to
develop a plan to scale it up 1 power of ten and then scale it down 1 and 2
powers of ten. This time they will need to explain how to scale up and scale
down, as well as demonstrate scaling up and down.
Questions to ask: Have one group demonstrate and explain how they scaled
up the lump of clay. They will have a cube with 9 cubes added to the original
in three directions (vertical, horizontal and upward)
Ask: did any group do something different? Ask groups that did something
different to explain and demonstrate.
Does it appear that all groups used the same amount of clay to scale up? How
can we determine if everyone used approximately the same amount? Yes, by
mass.
Ask one group to explain how they scaled the clay down one power of ten.
(They divided the clay into 10 even parts in three directions resulting in a
very small piece of clay). Ask if all groups used the same procedure. If any
group mentions a different procedure have them share and demonstrate.
Ask one group to explain how they scaled the clay down two powers of ten.
Ask if all groups used the same procedure. If any group did not, ask them to
share their procedure and example with the class.
What is similar between scaling up and scaling down by powers of 10? It is
always using a set of 10 per base unit.
What is different? With scaling up, you are making it bigger by adding 9 more
in all dimensions. With scaling down, you are removing 9 in all dimensions.
What is similar between the paper scaling and the clay scaling? Using the
same procedure
What is different between the paper scaling and the clay scaling? One only
had two directions to be concerned about and the other has three.
Are you creating a model? How or how are you not creating a model?
(4) Graphing and approaching zero not reaching zero
Using a projector and computer, open up excel (if you have graphical analysis,
it will work much better). One thing that is very difficult for students to
comprehend is the idea that we do not reach zero, but keep approaching zero.
So you are going to enter the numbers 1, 2, 3, and 4 for the x-axis and 1000,
100, 10, and 1 for the y-axis. Ask students to describe the shape of the line
once you have it graphed. Now add the number 5 for the x-axis and 0.1 for
the y-axis. Ask the students to describe how the graph has changed. Now
you will want to change the scale of the y-axis. Change it to go from 10 to 0
on the y-axis. Ask students to describe how the graph has changed. Add 6
for the x-axis and 0.01 for the y-axis. Ask the students how the graph has
changed. Now change the y-axis scale to 1 to 0. Ask the students how the
graph has changed. Now tell then you want them to predict what will happen
if you add 7 for the x-axis, and 0.001. Have some students volunteer to share
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responses. Now add these two numbers to your graph. Now ask them what
will happen if I changed the y-axis to go from 0.1 to 0?
What you want them to tell you is that each time, while it looks like the graph
is going to zero, upon closer examination, it is getting nearer to zero, but
there is always space between the line of the graph and the zero mark.
Science Notebook:
In reference to the graphing activity, have students use the following frame:
I noticed that as _____________________________________________, the
_______________________________________. I believe this happens because
________________________________.
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1. Atomic Target Practice
In this series of activities and discussions, students are learning about the
two regions of an atom: nucleus and electron cloud. In the following lesson
students will learn about the three subatomic particles and be introduced to
their properties: charge, relative mass, and location.
Learning Target:
I can identify the parts of an atom which made up its structure.
(nucleus, electron cloud, neutron, electron, proton)
Focus Question:
What is the overall structure of an atom?
Key Vocabulary:
Electron cloud, nucleus
Sequence of Experiences
(1) Model to Size to Atom Discussion
10 min
(2) Atomic Target Practice Activity
20 min
(3) Discussion of Atomic Target
10 min
(4) What’s Around the Nucleus?
10 min
Materials:
28 centimeters long strip of paper for each student
1 pair of scissors for each student
Flinn Atomic Target Practice Kit (A hint for constructing the cardboard: I
used the glue provided, but it did not work well. The wooden blocks fell off
after one group shot marbles at it. The second time I used wood glue and
mine have stayed together for two years.)
Copies of Student Handouts
Painters Tape (it releases better than any other tape)
White paper
2 magnets
(1) Model to Size to Atom Discussion
The Phantom’s Portrait Parlor Paper Cutting Activity from The Atoms
Family-The Mummy’s Tomb – Paper Cutting
http://www.miamisci.org/af/sln/phantom/papercutting.html
20
The Phantom wants to create life sized models of
atoms, and he wants your help! Help the Phantom
investigate the world of the very small by cutting a
28 centimeter strip of paper in half as many times
as you can. If you can cut the strip of paper in half
31 times you will end up with a piece of paper the
size of an atom.
Take your strip of paper and cut it into equal halves.
Cut one of the remaining pieces of paper into equal
halves.
Continue to cut the strip into equal halves as many
times as you can.
Make all cuts parallel to the first one. When the width
gets longer than the length, you may cut off the excess,
but that does not count as a cut.
How far did you get? Here are some comparisons to
think about!
Cut
14.0 cm 5.5"
1
Cut
7.0 cm 2.75"
2
Child's hand, pockets
Fingers, ears, toes
21
Cut
3
Cut
4
Cut
6
Cut
8
Cut
10
Cut
12
Cut
14
Cut
18
Cut
19
Cut
24
Cut
31
3.5 cm
1.38"
Watch, mushroom, eye
1.75 cm .69"
Keyboard keys, rings, insects
.44 cm
.17"
Poppy seeds
1 mm
.04"
.25 mm
.01"
.06 mm
.002"
.015 mm .006"
1 micron .0004"
Thread. Congratulations if
your still in!
Still cutting? Most have quit
by now
Microscopic range, human
hair
Width of paper, microchip
components
Water purification openings,
bacteria
.5 micron .000018"
Visible light waves
.015
micron
.0001
micron
Electron microscope range,
membranes
.0000006"
.0000000045" The size of an Atom!
Is there anything smaller? Yes, the size of an atom
nucleus would take about 41 cuts! Scientists use
advanced technology to explore the world of electrons
and quarks that are at least 9,000 times smaller than a
nucleus.
We cannot see anything smaller than an atom with our
eyes, even with the electron microscope. Physicists
study much smaller things without seeing them
directly.
Is there an end to the quest for the smallest and most
basic elements in our world? The search began with
the Greeks and continues as scientists search for the
Building Blocks of the universe. These things are far
beyond the range of sensory perception but not beyond
the range of human understanding.
22
(2) Atomic Target Practice Activity
For this activity, the teacher needs to have previously constructed the
mystery cardboard. It is important to give each of the boards a letter to keep
straight what boards have been tested by a group of students. You will also
need to demonstrate to the students how to set-up the white paper on top of
the cardboard. Go over with the students how to shoot the marbles and to
record the path. Divide students into groups. Groups of three work best for
this, but you may need to have larger groups. Explain that students are not
allowed to lift the cardboard up. If they have a lost marble, then contact you
for retrieval. I generally have a ruler to help with marble retrieval. Establish
your behavior expectations before allowing students to start testing.
Students should test at least three “boards,” you may want to keep them
moving two to the left or two to the right each time. By moving two, that
reduces the copying of data.
Student Handout
23
Atomic Target Practice
The following activity is adapted from Flinn Scientific Atomic Target Practice
Catalog number ap6496
Name _________________________________ Date ______________
Materials:
Masking tape
2 pieces of white paper per station
Pencil
Marbles
Unknown stations
Procedure
1. Do not lift any of the cardboard stations.
2. Tape two pieces of white paper together forming a square.
3. In the center of the cardboard, tape down the white square (the taped side
should be facing down). Record the letter of the station on the white paper.
4. Roll the marble with a moderate amount of force under one side of the
unknown. Observe where the marble comes out and trace the approximate
path of the marble on the white paper. For example, if the marble rolls
straight through, draw a straight line from one end of the sheet to the other.
Note: Do not press too hard on the paper and cardboard when drawing the
lines.
5. Working from all four sides of the cardboard, continue to role the marble
under the board, making observation and tracing the rebound path for each
marble roll. Roll the marble at least 20 times from EACH side of the box.
Vary the angles at which the marble is rolled.
6. After sketching the apparent path of the marble from all sides and angles, the
general size and shape of the unknown target should emerge “in the negative”
from the area where there are no lines (where the marble does not pass).
7. Form a working hypothesis concerning the structure of the unknown target.
Based on this hypothesis, repeat as many “targeted” marble rolls as
necessary to either confirm or revise the structure.
8. Show your final results to your teacher.
9. When given the ok, go to another station.
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Results:
1. In the boxes below, draw the predicted shape and include the letter of the
station.
2. How can the pathway into and out of the cardboard help you with
determining the shape underneath?
3. Many experiments in science ask for just three trials. Would three trials per
cardboard be sufficient evidence to determine the shape of the object? Why
or why not?
4. Provide an example of an object that may have been described using indirect
evidence.
5. How confident are you of your predicted shapes? Explain your reason for
your indicated confidence level.
6. Is your predicted shape a model? Why or why not?
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(3) Discussion of Atomic Target
How many of you are fairly confident you have predicted the correct shape?
What would make you more confident?
Many objects cannot be observed directly by scientists. They must collect
indirect evidence in the form of observations. The atom is very small and its
interior currently cannot be observed directly. When the basic structure and
parts of the atom were discovered, scientists could not even see the exterior
of an atom. So they were “shooting” in the dark. The experiment that
discovered the division of the atom into two main parts was known as the
Rutherford’s Gold Foil Experiment.
Show video here
http://www.youtube.com/watch?v=Q8RuO2ekNGw
How was your experiment similar to Rutherford’s?
What part of the experiment does the marble represent? The alpha particles
What part of the experiment does the cardboard represent? The gold foil
What does the object under the cardboard represent? The nucleus
What does your hand represent? The detector
How was the experiment modeling the Rutherford Gold Foil Experiment?
What does it mean to be modeling? Modeling refers to the action, or the
activity of modeling. The final product is the model.
(4) What’s Around the Nucleus
Teacher holds up two magnets. As the magnets get closer together, it
becomes harder and harder (requires more force) to bring them closer.
What is responsible for the magnets the increasing force needed? Magnetic
repulsion
Can you see it? No
How do you know it is there? By the observed behavior of the magnets
With atoms, we know it has a nucleus, but it is very hard to get a particle near
the nucleus. So this suggests something is ‘there’ but we cannot ‘see it,’ but
we infer it is there based upon the observed behaviors. The region around
the nucleus is called the electron cloud.
26
2. Protons, Neutrons and Electrons
Learning Targets:
I can identify the parts of an atom which made up its structure.
(nucleus, electron cloud, neutron, electron, proton)
I can distinguish the parts of an atom based upon mass and charge.
(proton, electron, neutron)
I can demonstrate, in words and pictures, how the size of an atom
compares to a visible object.
I can explain how models are different from reality.
I can distinguish between different forms of models.
I know what holds an atom together.
Focus Questions:
What are the subatomic particles and where are they located?
What are the relative charges and masses of the subatomic particles?
How does the structure of the solar system compare to the structure
of an atom?
Key Vocabulary:
Proton, neutron, electron, relative mass, relative charge
Sequence of Experiences
(1) Introduction of the characters, individual, whole
class
10 min
(2) Where Do These Shocking Characters Reside?,
whole class
10 min
(3) If You Build…. It Will Matter, individual or paired
25 min
(4) Wrapped Up with a Bow?, whole class discussion
27
25min
(5) Solar System Vs Atom Event, whole class
demonstration and discussion
25 min
(6) We’re Stuck Like Glue, whole class demonstration
and discussion
10 min
Materials:
Solar System Activity:
15, 4” by 4” cardboard pieces
1 box of Pins with colored round balls
Very long measuring tape, at least 100m
3 meter sticks
Optional: If solar system model activity is conducted outside for space, you
will want rocks to secure the cardboard pieces.
Computer with projection
Find URL and enter it here for Cathode Ray Experiment:
http://www.youtube.com/watch?v=XU8nMKkzbT8&feature=related
Computer lab for students (working in pairs is acceptable but individual
would be good)
Atom Builder Website: http://phet.colorado.edu/en/simulation/build-anatom#software-requirements
Student Handouts for Atom Builder
(1) Introduction of the Characters
What did we learn about the structure of the atom so far? It has a nucleus
and an electron cloud.
What evidence did we gather to establish this division? The paper cutting
experiment established how small the atom is and the atomic target
practice for the central location of the nucleus. A demonstration using
magnets established the existence of the electron cloud. We watched a
video about Rutherford’s Gold Foil Experiment
In our next series of investigations, we will look at some characteristics of
the subatomic particles: proton, neutron, and electron.
Pre-assessment entrance slip:
Place the following in order of size (not mass) from smallest to largest:
atom, cell, electron, electron cloud, neutron, nucleus, proton
Explain your reasoning below.
Correct Order: electron, proton and neutron, nucleus, electron cloud,
atom, cell
28
(Optional: I collect the entrance slips with names on them to return to
students at the end of the lesson series to make corrections. You may not
wish to do this with your students.)
(2) Where Do These Shocking Characters Reside?
For this activity, you will show a short clip of a cathode ray tube. Have
the students observe and take notes about their observations in their
notebooks. The video is about 2 minutes long. Questions for students to
answer:
How does the ray inside the tube respond to the magnet the first time? It
moved away from the magnet. (or up)
When the magnet is reversed, how does the ray respond? It moved
toward the magnet (or down).
What do you know about the charges when objects are attracted to one
another? That they have opposite charge direction
What do you know about the charges when objects are repelled from one
another? That they have similar charge direction
What does the behavior of the cathode ray tube suggest about the ray?
The ray has a charge and it is composed of particles.
Do you know what the particles could be from the evidence presented so
far? NO!
Why or why not?
(3) If You Build…. It Will Matter
Students will need access to a computer to do this activity. Ideally it
would be one student per computer, but this is rare. Two students per
computer would be acceptable. Each student needs to record the
information on a page. If they do not, then they will not have the
information to refer to later. Give them the data sheet, but not the
question sheet. Provide question sheet as students complete, but this
should not be finished by all students before starting discussion.
Take students to the computer lab. Demonstrate how to get to the
activity and how to move the items around. Point out where they should
look. I would do a first example with the class and then give them time to
create an additional 17. When all students have completed collecting
data, it would a good time to return to class. The students may not be
finished with answering the questions, but I have found it best to move
my students back to the room as soon as all legitimate computer use has
completed.
Student Handout Follows
29
Name _____________________________________
Period ________________
Date__________
The Atom Builder
Directions: Go to http://phet.colorado.edu/en/simulation/build-an-atom#software-requirements
Click on the build an atom picture or the green RUN NOW box (this is version 2.0). By moving red
protons, grey neutrons, and blue electrons into the Bohr model of the atom, fill-in the table below.
From the data collected, answer the questions below the table. In the protons, neutrons and
electrons boxes indicate how many and where they are found on the model. For mass number, write
down the number indicated in the middle box to the right of the model. If it provides a name is an
element, record the name under ‘what did you make?’. In the final column, indicate if it is charged or
not charged. If it is charged, indicate if it is a positive or a negative charge.
Trial
Protons
Neutrons
Electrons
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
30
Mass
Number
What did you
make?
Is it charged or
neutral?
(indicate charge
as + or -)
1.
Where do the protons go as you add them to your model?
2.
What is the name of this region?
3.
Where do the neutrons go as you add them to your model?
4.
What is the name of this region?
5.
Where do the electrons go as you add them to your model? What is the name of this region?
6.
When your “atom” has a positive charge, what do you notice about the ratios between
protons and electrons?
7.
What does this suggest about the charge of a proton?
8.
When your “atom” has a negative charge, what do you notice about the ratios between
protons and electrons?
9.
What does this suggest about the charge of an electron?
10. Looking at your data, what do you think is the charge of a neutron?
11. Using your mass data, which particle or particles contribute the most to the overall mass of
an atom?
12. What does this tell you about the mass found in the center of an atom compared to the mass
found in the outer region?
13. Which of the three particles have nearly equal masses?
31
(4) Wrapped Up with a Bow?
Review the three subatomic particles and the two major divisions of the
atom with a series of questions and supporting evidence.
What are the two sections of the atom? Nucleus and electron cloud
What did we do to discover the ‘shape of a nucleus?’ the atom builder
game or we shot marbles under cardboard over and over again. We
traced the path into and out of the cardboard and made educated guesses
after several trials about the shape.
Where is the nucleus located? In the center
How do you know that? From the atom builder game
What subatomic particles are found in the nucleus? Proton and the
neutron
How do you know that? When we moved a proton or a neutron into the
“atom template” they always moved to the center.
What is the charge of a proton? Positive
How do you know that? Whenever we added a proton to an atom, the
charge became positive or became more positive
What is the charge of a neutron? It does not have a charge.
How do you know that? When neutrons were added to the atom builder
game, they never changed the charge. If it was positive, it stayed the
same positive value. If it was negative, it stayed the same negative value.
If it was neutral, it stayed neutral.
What could you add to the atom to make the positive charge to become
neutral? An electron
What is the implied charge of an electron? It is negative
How do you know? Playing the atom builder game.
Where does the electron go in an atom? The outside region or electron
cloud
Question if they give the first answer:
What is the name of this outside region? The electron cloud
Question if they give the second answer:
Where is the electron cloud? The region surrounding the nucleus on the
outside.
How do you know that? By playing the atom builder game, the electrons
always when to the outside rings
So we have three subatomic particles in the atom: add them to the black
box with the ‘?’ Then add plus sign and negative sign to the proton and
electron.
Now, we have learned about another property of protons, electrons and
neutrons from playing the game. It has to do with relative mass.
Which of the three subatomic particles has the smallest mass? The
electron
How do you know? When an electron was added in the atom builder
game, the total mass did not change or it changed very little.
Did the mass change when you added a proton? Yes
Did the mass change when you added a neutron? Yes
32
It the mass change more with a proton or a neutron? It was about the
same or it was the same change for each.
So an electron is much smaller than a proton and a neutron, but a proton
and a neutron have about the same mass according to the atom builder
game.
Have students create in their notebooks a summary of the findings. A
table with columns: subatomic particle, location, charge, relative size,
relative mass, and then a description of nucleus and electron cloud with
drawing would be good.
Particle
Location
Charge
Relative
Size
Relative
Mass
Now ask students, what do you think is the general charge of the nucleus?
Positive
Why? Because the protons have a positive charge and are found in the
nucleus. Neutrons do not have a charge so the only charge in the nucleus
is due to the protons. (Make students state the neutrons because some
students get this confused. Possible neutron misconceptions are: it has a
negative change because it starts with an n, and it has both a positive and
a negative because it is just a proton and electron stuck together)
What do you think is the general charge of the electron cloud? Negative
Why? Because electrons have a negative charge and are found in the
electron cloud.
Have students add this information to their notebook entries about the
electron cloud and the nucleus.
Suggested Frame
I know the charge of the nucleus is ___________________, because
_______________________.
I know the charge of the electron cloud is ______________, because
______________________.
(6) Solar System Versus Atom Event
1. You will need at least 14 volunteers. Explain to the class that you need
several ‘helpers.’ Each helper will either be a planet or a layer of electrons.
33
2. Give each volunteer a piece of cardboard, a pin, and a planet name or electron
level paper. If going outside, give each volunteer a rock to use as a paper
weight.
3. Have the entire class go out to the long hallway or to the outside side walk.
Bring with you 3 meter sticks and 100 meter measuring tape. Also, you
should bring with you two pieces of cardboard and the box of pins.
4. Instruct students to stand against the wall or along the edge of the sidewalk.
Hold up one pin (using one that has a yellow top would be perfect). Explain
that as a group we are going to set-up our solar system based upon the sun’s
diameter being represented by the yellow pin.
5. Next, ask all the students that are carrying planets to estimate where they
think their planet is located relative to the sun. Emphasize that they do not
need to stay in order from the sun at the time.
6. When all planets and Pluto have been placed. Ask the class to look and then
explain you will now provide the correct measurements.
7. Ask, ‘What is the name of the first planet from the sun?’ Direct the student in
charge of Mercury to step forward and hand them one meter stick.
8. Give measurement for Mercury 12.5 cm
9. Repeat with Venus (23.3 cm)
10. Repeat with Earth (32.2 cm)
11. Repeat with Mars (49.2 cm)
12. Repeat with Jupiter (168 cm)
13. Repeat with Saturn (308 cm)
14. Repeat with Uranus (619 cm)
15. Repeat with Neptune (970 cm)
16. Is this a model? Yes. How do you know? Well the planets are much larger.
17. Is this model scaled up or scaled down? It is scaled down. How do you know?
The planet earth is what we are standing on, but now in a scaled down model
we are looking at the entire planet Earth. What does that mean for the
distances between the planets here, in our model, compared to the actual
solar system? The distance is much greater.
18. Ask the students what is found between the planets. Answers: comets,
asteroids, dust, empty space, meteoroids, dwarf planets, satellites, moons, etc.
19. Now, we are going to use another pin (hold up) and this pin represents the
nucleus of an atom. Place the pin in cardboard on the ground in line with the
sun.
20. Now, three students have been give “electron levels” these are the 1s, 2s, and
3s. Ask the class to estimate where they think the 1s would be. Have the
student in charge of the 1s place it on the ground. Repeat with the 2s and 3s.
34
21. Now that the three electron levels are placed on the ground. Announce that
you are going to give the actual measurements if the pin represents the
nucleus.
22. Have the student in charge of the 1s pick it up. The 1s electrons are located
4.4 m.
23. Next, have the 2s student pick up the cardboard and announce, the 2s
electrons are 8.8 m.
24. Repeat with the 3s. The 3s electrons are 17m. Watch until the student stops.
25. Repeat with the 4s. The 4s electrons are 25m.
26. Repeat with the 5s. The 5s electrons are 70m.
27. Repeat with the 6s. The 6s electrons are 144m.
28. Now ask the class, what do you notice about the two models? (Ideal answer:
all of the solar system is found inside the first electron levels)
29. Ask the students what is found between the electron levels? (Wait for a
moment; someone may suggest the correct answer of empty space). If no
responses after waiting, ask the students what is found most often between
the planets? (Empty space)
30. Ask students to pick-up their planets and electron levels and return to the
classroom to continue the discussion.
31. In the classroom, collect all the pins, cardboard and papers (really count the
pins!!!). Now review what was observed in the hallway or outside on the
sidewalk. Next, ask students: “By percentage which has more empty space:
our solar system or an atom?” The atom. And how do you know? When the
atom was scaled up and the solar system was scaled down so they were using
the same scale, the atom was bigger.
32. Direct students to write down what they observed in the demonstration and
to write down the conclusions in science notebooks.
33. Now one question that we had not answered is: which is larger, the electron
cloud or the nucleus? The electron cloud is larger. How do we know this?
From the model of the atom compared to the solar system.
34. Thinking about the mass of an atom, where is the majority of the mass found?
In the nucleus. So what does that suggest about the density of the nucleus? It
is very dense. How does the density of the nucleus compare to the density of
the electron cloud? The nucleus is significantly more dense because it has a
limited amount of space for a large amount of mass while the electron cloud
has every little mass in a large space. How do we know this? From the atom
builder game and from the solar system/atom model activity.
35
Suggested Notebook Frame
One similarity between to the two models was _____________________________ but a
difference was ________________________________. I now know _________________ because
______________________.
Solar
System
object
Miles from
Sun
Centimeters, if
Sun diameter =
3 mm
Sun
Diameter =
864,100 mi
-
Mercury
36,000,000
12.5cm
Venus
67,100,000
23.3cm
Earth
92,900,000
32.2cm
Mars
141,700,000
49.2cm
Jupiter
483,400,000
168cm
Saturn
Uranus
886,100,000
1,782,700,000
308cm
619cm
Neptune
2,793,100,000
970cm
Atomic
Object
Nucleus
n=1
electron
n=2
electron
n=3
electron
n=4
electron
n=5
electron
n=6
electron,
aka
valence
electrons
fm* from
nucleus
(gold atom)
Diameter =
30 fm
Meters if
Au nucleus
= 3 mm
43,750
4.4m
87,500
8.8m
175,000
17m
350,000
35m
700,000
70m
1,400,000
144m
*1 fm = 10-15 meter
36
-
Tags for Identifying Planets and Electron Levels
1s
Mercury
Venus
2s
Earth
3s
Mars
4s
Jupiter
5s
Saturn
6s
Uranus
Sun
Neptune Nucleus
The solar system activity has been adapted from an activity developed by Martin
Brock, Chemistry Professor at Eastern Kentucky University.
37
(7) We’re Stuck Like Glue?
Review the parts of the atom to start the lesson. You may have an
entrance slip: draw and label the parts of an atom.
Collect the entrance slip and ask students the following question: What
do you think keeps the nucleus and the electron cloud together? It is the
like charges which are attracted to each other. (electrostatic forces) How
is this like magnets?
38
3. Model Refining
Learning Targets:
I can analyze multiple, basic atomic structure models for advantages
and limitations.
I can identify the form of model to use.
Focus Questions:
What are the advantages and limitations of atom models?
How do you determine which atom model to use?
Key Vocabulary:
Model
Sequence of Experiences
(1) Advances of Models
25 min
(2) Which One?
25 min
Materials:
Copy of entrance slip (if not done in science notebook)
Computer, projector
One of the model organization schemas
Access to the videos (will need to download from sharepoint)
What do we know about the atom so far? How can we organize the internal
structure of the atom? How is this model an improvement from the previous
model? How does this model incorporate what we have learned so far?
(1) Advances of Models
Comparing the attraction of the nucleus to the electron cloud with
magnets is a type of model.
We have been working on developing a model of the atom based upon a
series of activities. What we have at this point is three models. Two
models are of the internal structure: Rutherford, and Bohr model.
Video of Rutherford Model (about 1:30 minutes)
http://www.youtube.com/watch?v=bSEOOMs5VNU
Video of Bohr Model (about 40 seconds):
http://www.youtube.com/watch?v=wCCz20JOXXk&NR=1
The third is the atom as a particle model. Pass out model summary pages
to students.
39
The following is just an example. You should modify to meet your needs.
Plus you can make it pretty.
Model:
Description:
Drawing Example:
What it can do/show:
What it cannot do/show:
List any similarities to other models:
40
Model Matrix
Model
Description
Drawing
Example
What it can
do/show
41
What it cannot
do/show
List similarities
to other models
Model
Particle
Rutherford
Bohr
Description
Drawing
Example
What it can
do/show
What it cannot
do/show
Spherical shape, only
shows the outside
It can show the
relationships between
particles, such as
increasing temperature
leads to particles that
are farther apart. It can
demonstrate molecule
ratios. Phase changes
It cannot show any of
the interior structure of
the atom.
Spherical, is 3-D, but
drawn flat.
It has protons in the
center with electrons
outside it at equal
distance.
It can show some of
the interior structure
(protons and neutrons)
It does not show the
amount of empty
space in an atom, it
does not include
neutrons, no electron
shells. Nucleus is not
dense, has space in it.
Spherical, but drawn
flat. It is 2-D
With Bohr it has
protons and electrons
with two sections
(electron cloud and
nucleus)
It has protons,
neutrons and electrons.
Neutrons and protons
are packed in the
center. Electrons are
on concentric rings
around the nucleus
with space between
rings, all space is the
same distance.
It can show interior
structure of the atom
include rings of
electrons that are not
equal distance.
It does not show all
the empty space, it is
not to scale.
Stationary.
Spherical, is 3-d but
drawn flat.
With Rutherford, it has
protons and electrons
and two sections the
electron cloud and
nucleus)
42
List similarities
to other models
(2) Which One?
Why do you think we have multiple models? Students will provide various
reasons. When any student suggests ‘for different situations,’ that is the
answer you want.
43
4. Matter and Atoms are Conserved
Learning Targets:
I can modify the definition of matter (to include the concepts of atom
and element).
I can explain the relationship between atoms and the conservation of
matter.
I can use the existence of atoms to demonstrate the conservation of
matter.
I can interpret evidence which supports the conservation of matter.
Focus Question:
What is some evidence which supports the conservation of matter?
Key Vocabulary:
Matter, Conservation
Sequence of Experiences
(1) Atoms Matter…
10 min
(2) So Atoms Count
10 min
(3) Discussion of Atoms and the Conservation of
Matter
10 min
Materials:
Vinegar
Baking Soda
20oz bottle
Tissues
Scale (prefer digital with no decimal places)
Formative assessment What is Matter? Sheets to pass around
Formative assessment probe, ‘Is it Matter?’, circle sheet for all students
(1) Atoms Matter…
Students will have some concept of what is matter prior to the 8th grade
as this term has been used since the 5th grade, but it has been
continuously edited. To discover what the students already know or at
least think they know about matter, start with a formative assessment
strategy known as Chain Notes (from Science Formative Assessment: 75
Practical Strategies for Linking Assessment, Instruction and Learning, pp.
44
62-65). For this to work, and to limit time, you will want to have two
chain notes, one for each half of the class. At the top of the paper is ‘What
is Matter?’ and after this students will add sentences about what they
know about matter. Students may add new ideas or elaborate upon
others, but they should not repeat. When all the students have had a
chance to write something on the paper, you need to collect the papers.
Quickly scan and share a few at random. You may now us a survey
method for the statements you read. Thumbs up or down for agreeing or
disagreeing or they may have agree/disagree cards to hold up.
For very large classes, you may wish to break it into group circles of 6-7
students.
(2) So Atoms Count
So matter is anything that takes up space and has mass. From our earlier
activities, do you think matter is composed of atoms? If so, what evidence
do you have to make this claim? (many might suggest the solar system
activity, but they also have the atom builder game in which the mass of
the atom changed when protons and neutrons were added). Now have
students do the following probe. At the end, ask some students to share
their reasoning. You are looking for it has mass AND it is composed of
atoms. All but light, and sound should be circled. Light and sound are
forms of energy which is not composed of atoms, and does not have mass.
Is It Matter? Probe
Circle all the items below that you believe are matter.
Hair
Light
Aluminum Foil
Air
Clouds
Sound
Water
Bone
Tree Branch
Mirror
Explain why you believe these items are composed of matter.
____________________________________________________________________________________
____________________________________________________________________________________
____________________________________________________________________________________
____________________________________________________________________________________
45
Is It Matter? Probe
Circle all the items below that you believe are matter.
Hair
Light
Aluminum Foil
Air
Clouds
Sound
Water
Bone
Tree Branch
Mirror
Explain why you believe these items are composed of matter.
____________________________________________________________________________________
____________________________________________________________________________________
____________________________________________________________________________________
____________________________________________________________________________________
Suggestion: have students paste this into their notebook.
The correct answer is to circle all but light and sound. Many may select
light because of the dual nature of light or that they have heard the
phrase is behaves like a wave and a particle. Anything that is composed of
atoms is matter. Anything that only uses matter to pass (i.e. a wave) is a
form of energy.
(3) Discussion of Atoms and the Conservation of Matter
All matter is composed of atoms. What happens to the atoms in water
when the water evaporates? They move apart and move faster. Do you
think the mass of an atom changes? No Why or why not? Because the
mass of an atom is primarily due to the protons and neutrons. Protons
and neutrons are not lost during a phase changed. What about with a
chemical change? No, again protons and neutrons are not destroyed. So
let us test. We have some vinegar and some baking soda. Pour vinegar
into the bottom of the bottle and then add baking soda to the bottle by
placing it inside tissue paper. Tightly seal bottle. Carefully obtain the
mass of the bottle without mixing on the scale. Now shake it! Ask
students to make observations. Now obtain the mass on the scale. (It
should be the same). Now comment about how the sides of the bottle are
not as flexible as they were at the start.
Now return to the original question, do you think the mass of an atom
changes when it becomes a gas? No While the reaction was a chemical
reaction, the mass stays the same. So the atoms must retain their
property ‘mass’ during changes. For mass to change, it must escape the
system or it must enter the system.
46
Have students record the results of the test in their notebooks. It may be
a good idea to have students record their predictions and then the results
in the notebooks. Students must elaborate to the reason the mass stays
the same EVEN when a gas is produced.
Suggested Science Notebook Frame
I observed ______________________________. This/these observations suggest
______________________________________.
47
5. Scaling Up, Part 2 with Elements
Learning Targets:
I can distinguish between different forms of models.
I can define an element. (single type of atom)
I can classify atoms into element categories.
Focus Questions:
What is an element?
How do atoms and elements compare?
Key Vocabulary:
Element
5 min
(1) Scaling up, just a bit
10 min
(2) PowerPoint Power of 10
(3) Ummm……element
5 min
(4) Sorting A’s and E’s
15 min
5 min
(5) Discussion
Materials:
Computer
Projector
File on Powers of 10
Cardstock
Copies of the blank powers of 10
Baggies with items from the powers of 10 handout for students to organize
Sets of A and E Cards for each group of students
(1) Scaling up just a bit
At this point, we have focused upon the very small piece of matter known
as the atom. All of the matter around us is made of atoms. I am about to
show you a presentation starting with the size of an atom (the outside) to
the Earth from space. Using the scale template and the baggie of items,
place these items on the line which you think best represents the size or
‘scale’ of the object. (Pause) I want you to write down in your science
notebook, your estimated diameter for one atom of Xenon. (Xe)
Pictures are found below:
48
Length of a Marathon
Length of School Bus
Virus
Gravel
Pollen
Clay Particles
Sand Particles
Rain Drop
Xenon Atoms
49
Water Molecule
Cells (cancer)
Mosquito
Comparing Powers of Ten
(Measures in Meters)
10-9
10-8
10-7
10-6
10-5
10-4
10-3
10-2
10-1
100
101
102
103
104
105
Can you think of any items that are larger than 105?
Can you think of any items that are smaller than 10-9?
10-10
Atomic Scopic
Microscopic
Macroscopic
50
Land scopic
(2) PowerPoint Powers of 10 in reverse
Start the PowerPoint presentation. Take time to point out the scale and
the image. The first image is from IBM. Using nanotechnology and Atomic
Force Microscopy, they moved 32 Xenon atoms into the letters IBM.
Continue with the slides until you are outside the Earth.
Now return to your original set of items. Rearrange the order based upon
the information from the video. Record in your science notebook the final
arrangement of your items.
(3) Umm….. element
The study of chemistry has already involved learning a lot of new words
which we have added to our word wall. Today, we are going to add yet
another word: element. Have you heard of this word before? If so can
your share with us where you have heard the term? How was the term
used? (heating element, and the car model element are the expected
answers at this point)
An element is a specific type of atom. In the atom builder game, you may
have noticed that the symbol or element name changed only when you
changed the number of protons. An element is therefore defined by the
number of protons.
Please write down in your science notebook, how an element is defined.
(4) Sorting A’s and E’s
Explain to students they will use the cards to sort them into like element
groups using the criteria for an element. When students have completed
this activity, they will record the groups in their science notebooks. Then
they need to provide a reason for the cards that are found in a like group.
Pass out a set of cards to each group of students.
Circulate around the room to keep students on task and to answer
questions.
(5) Discussion
What determines if an atom is a specific element? The number of protons.
What is a difference between an atom and an element? Atom can have
any number of protons, but an element has a specific number to identify it.
What is a similarity between an atom and an element? They both have the
same parts: nucleus, electron cloud, protons, neutrons, electrons.
51
What information would you need to determine if your atom card was the
element carbon? The number of protons the atom has and the number of
protons required for the element to be carbon.
Suggested Science Notebook Frame
An element is like an atom because __________________________.
An element is unlike an atom because _______________________.
52
Atom Cards for Sorting: Print on Cardstock for Longevity
Electrons: 8
Protons: 8
Neutrons:
Mass: 21
Electrons: 11
Protons: 11
Neutrons: 10
Mass: 21
Electrons: 6
Protons: 6
Neutrons: 6
Mass: 12
Electrons: 8
Protons: 8
Neutrons: 11
Mass: 19
Electrons: 11
Protons: 11
Neutrons: 12
Mass: 23
Electrons: 5
Protons: 5
Neutrons: 11
Mass: 16
Electrons: 7
Protons: 7
Neutrons: 8
Mass: 15
Electrons: 4
Protons: 4
Neutrons: 6
Mass: 10
Electrons: 9
Protons: 9
Neutrons: 10
Mass: 19
Electrons: 9
Protons: 9
Neutrons: 6
Mass: 15
Electrons: 6
Protons: 6
Neutrons: 8
Mass: 14
Electrons: 8
Protons: 8
Neutrons: 9
Mass: 17
Electrons: 5
Protons: 5
Neutrons: 5
Mass: 10
Electrons: 3
Protons: 3
Neutrons: 3
Mass: 6
Electrons: 4
Protons: 4
Neutrons: 7
Mass: 11
Electrons: 7
Protons: 7
Neutrons: 9
Mass: 16
Electrons: 6
Protons: 6
Neutrons: 7
Mass: 13
Electrons: 4
Protons: 4
Neutrons: 5
Mass: 9
Electrons: 10
Protons: 10
Neutrons: 10
Mass: 20
Electrons: 5
Protons: 5
Neutrons: 6
Mass: 11
Electrons: 3
Protons: 3
Neutrons: 6
Mass: 9
53
6. Mendeleyev for a Day (or days)
Learning Targets:
I can classify substances using reactivities into like groups (families).
I can describe patterns from periods and families from the periodic
table.
I can predict missing elements based upon existing pattern.
I can identify chemical trends using atomic numbers and data in
tables/graphs (flammability, and reactivity).
I can identify physical trends using atomic numbers and data in
tables/graphs (density, boiling point, and solubility).
Focus Question:
What is meant by periodic?
Key Vocabulary:
Trend, Atomic Number, Periodic
Sequence of Experiences
1.
Card Sort 1
2.
Discussion of Card Sort 1
3.
Card Sort 2
15 min
5-10 min
25 min, first day
20 min, second day
4.
20 min
Discussion
Materials:
Sets of cards
Envelopes
Separated Undiscovered Element Cards
Scissors
1. Card sort part one
Distribute cards to groups and explain that these cards need to be sorted into
like groups. For membership in the group, a ‘rule’ must be created. For
example, I could create a rule that to be in the group every member must be
green. For the cards that do not fit, a new rule must be created for them. You
may have as many groups as you like, but for each group, you must have a
54
rule. In your science notebook, record the rules for each group and the
‘members’ found in each group.
2. Discussion of part one
Have students put all cards in envelopes and collect envelopes (so that they
do not play with cards during discussion).
Have each group share the ‘rules’ they have created. The point of doing this
is to establish that not all groups created the same rules, but some did. When
scientists begin to develop classification schemes, some groups use the same
classification rules and others use different rules. How do classification
schemes become established, especially when there are multiple
suggestions? Pause for students to provide ideas.
The method which the rules and classifications provide the greatest
predictive power and require the fewest ‘exceptions’ generally becomes the
scientifically accepted method. (my aside, oh if only this applied to spelling)
3. Card sort part two
For card sort two, your group is going to work together to try to fit a puzzle.
Your cards are going to form seven groups. All seven groups have a rule.
Give student groups time to establish seven groups with a rule for each.
Pause and ask for groups to share ideas about rules they have used.
Now ask students to look carefully at the cards, what properties have been
used and what properties have not been used which are found on the cards?
Could you use some of the additional properties?
Now, for the extra challenge, your group needs to create seven groups with
the group members ranked. Put your top member at the top of the group
column and the last member at the bottom.
Pause for groups to work.
Ask groups how did they determine rank?
Now explain that we are going to try to bring the groups together so that the
groups increase left to right and top to bottom. Also, each group must still
have a rule for membership. It is acceptable to change rules and to move
cards around. You may even have up to four ‘holes.’ Holes may be filled with
‘undiscovered element cards.’ These cards may be obtained from the front of
the room (or where you wish to have them).
Pause and allow for work. If you notice too much frustration, provide hints
such as did you use all the properties on the cards? Can rules have
exceptions? (This is for the mass issue) Are you thinking about the
Compounds with ‘H’ category?
55
4. Discussion
Now that we have rules for each of our seven categories, can someone share
one from the first column?
Second?
Third?
Forth?
Fifth?
Sixth?
Seventh?
What is the general rule for mass going left to right? Increasing
Going from the top to the bottom? Increasing
What mass would you predict for the missing element 1? Explain how you
have determined your predicted mass?
Missing element 2? Explain how you have determined your predicted mass?
Missing element 3? Explain how you have determined your predicted mass?
Do you think missing element one will reaction with H? What about missing
element 3, will it react with H?
The following data is just like the data the Mendeleyev used when he
designed the periodic table. Pass out periodic tables. Ask students to review
the masses? What is the general rule left to right and up and down?
What do you think periodic means? How does this relate to the table?
Provide evidence from the table.
The general rules are known as trends. Remember the term element? What
characteristic is used to distinguish elements? number of protons
Looking at the periodic table, I can easily determine the number of protons
for every element. Do you have any idea how I can do that? Pause
I am looking at the individual boxes and the whole numbers found within
them. (Quick math review: What is a whole number?) The whole number of
oxygen is eight, so it has eight protons. The whole number is called the
atomic number. Take time for students to write down the terms: trend and
atomic number with descriptive criteria in their science notebooks.
Practice: how many protons does Na (Sodium) have? 11
How do you know? That is the whole number in the box with the symbol Na
for sodium.
How many protons does Zn have and how do you know? 30 because that is
the whole number in the box with the symbol Zn for Zinc.
56
Pass out very short proton quizzes (there are three below):
How many protons does P (phosphorous) have? Explain how you know.
What does the term atomic number refer to?
How many protons does Br (Bromine) have? Explain how you know.
What does the term atomic number refer to?
How many protons does Se (Selenium) have? Explain how you know.
Cards for Mendeleyev for a day part two
57
Barney
B
Blank
Element Mass: 40
Physical State: monatomic gas
Melting Point: -190°C
Compounds with H: none known
Compounds with Cl: none known
Cassie
Donatello
C
D
Element Mass: 32
Physical State: yellow solid
Melting Point: -113°C
Compounds with H: CH2
Compounds with Cl: CCl2, C2Cl2
Element Mass: 12
Physical State: soft black solid
Melting Point: 3550°C
Compounds with H: DH4
Compounds of Cl: DCl4
Frantic
Gopher
F
G
Element Mass: 9
Physical State: steel gray solid
Melting Point: 1280°C
Compounds with H: FH2
Compounds of Cl: FCl2
Element Mass: 19
Physical St.: pale yellow diatomic gas
Melting Point: -220°C
Compounds with H: GH
Compounds with Cl: GCl
58
Isis
I
Undiscovered Element
Element Mass: 35
Physical St.: green-yellow diatomic
gas
Melting Point: -101°C
Compounds with H: IH
Compounds with Cl: ICl
Jinx
Kermit
J
K
Element Mass: 24
Physical St.: silvery white metallic
solid
Melting Point: 640°C
Compounds with H: JH2
Compounds with Cl: JCl2
Element Mass: 28
Physical State: lustrous gray solid
Melting Point: 1410°C
Compounds with H: KH4
Compounds of Cl: KCl4
59
Penelope
P
Undiscovered Element
Element Mass: 31
Physical State: solid
Melting Point: 280°C
Compounds with H: PH3
Compounds with Cl: PCl3, PCl5
Quirky
Ralphie
Q
R
Element Mass: 23
Physical State: soft silvery metallic
solid
Melting Point: 98°C
Compounds with H: RH
Compounds with Cl: RCl
Element Mass: 79
Physical State: solid
Melting Point: 221°C
Compounds with H: QH2
Compounds with Cl: QCl2
Timmy
T
Undiscovered Element
Element Mass: 39
Physical St.: soft silvery metal
Melting Point: 64°C
Compounds with H: TH
Compounds with Cl: TCl
60
Utopia
U
Undiscovered Element
Element Mass: 20
Physical St.: monatomic gas
Melting Point: -249°C
Compounds with H: none known
Compounds with Cl: none known
Willie
Xenia
W
X
Element Mass: 7
Physical St.: soft silvery metallic solid
Melting Point: 181°C
Compounds with H: WH
Compounds with Cl: WCl
Element Mass: 80
Physical State: red-brown liquid
Melting Point: -7°C
Compounds with H: XH
Compounds with Cl: XCl
Yo-Yo
Zeus
Y
Z
Element Mass: 16
Physical State: diatomic gas
Melting Point: -218°C
Compounds with H: YH2, Y2H2
Compounds with Cl: YCl2
Element Mass: 75
Physical State: gray solid
Melting Point: 817°C
Compounds with H: ZH3
Compounds of Cl: ZCl3
61
7. Sorting by Property/Reactivity
Learning Targets:
I can identify groups of elements with similar properties (metals, nonmetals and non-reactive)
I can use reactivities to classify substances into like reactivity groups.
I can rank order reactivity based upon data patterns.
Focus Question:
What trends can we identify using reactivities and the periodic table?
Key Vocabulary:
Family, Period
Sequence of Experiences
(1) Metal or Not with discussion
15 min
(2) Reaction Tests
20 min
(3) Reflection and Discussion
20 min
(4) Trend Detectives
45 min
Materials:
Metal/non-metal cards
Well plates
Metal samples (Ca, Zn: Mg, Ca: Mg, Al)
1M HCL
Plastic Pipets
Goggles
Water
Cardstock
Copies of MSDS sheets Ca, Zn, Mg, Al, and HCl (1M concentration)
Forceps/Tweezers
Copies of the Periodic Tables for melting point, boiling point, and density
(about 6 of each so that each group of 2-3 has one)
A copy of a Periodic Table in Spanish is also available
(1) Metal or Not
Teacher note: Many individuals tend to think of metals as only the
transition elements. They do not classify calcium, or magnesium as metals.
62
In this activity, students will confront their misconception of metals versus
non-metals.
Ask students, list three examples of a metal. Pause. Describe two
properties that a metal has. Pause. Describe a test you would conduct to
determine if an unknown was a metal.
Have students share examples of metals. Record the student responses on
the board. If students give answers unrelated to chemistry, record the
response but explain why these are inappropriate. If it gets out of hand,
state this earlier.
Lets us look at the periodic table, where are the metal elements identified?
On the left side
The location of metals and non-metals on the periodic table is another
trend. Metals are located to the left of the stair-step line (it is under boron,
between Aluminum and Silicon, between Germanium and Arsenic,
between Antimony (Sb) and Tellurium and between Polonium and
Astatine).
The periodic table also has clear rows and columns. The columns are
often called families and the rows, periods. Direct students to record these
descriptors of the terms family and period in their science notebook. They
will need these to complete their laboratory experience.
Ask students: Are Fluorine (F) and Chlorine (Cl) in the same family or
period? How do you know? Family, they are in the same column.
Ask students: Are Tin (Sn) and Silicon (Si) in the same family or period?
How do you know? Family, they are in the same column.
Ask students: Are Potassium (K) and Scandium (Sc) in the same family or
period? How do you know? Period, because they are in the same row.
Ask students: Are Lithium (Li) and Magnesium (Mg) in the same family or
period? How do you know? They are not in the same family or period
because they are not in the same row or column.
(2) Reaction Tests
For this test, students must be reviewed about safety procedures before
beginning. You may wish to have a short safety/procedure quiz after
reviewing the procedure with the students. Make sure you have the MSDS
sheets available in the unlikely event of a student accident. Students must
wear goggles (over eyes, not their neck or hair) and wash hands at the end
of the laboratory clean-up.
63
Students will need to use forceps to remove a calcium sample and place in
two wells. Using forceps, one Mg sample into two other wells. Next, one
Al sample into a well and one Zn sample into a well. Return to their lab
stations. At the lab station should be one pipet of 1M HCl and one pipet of
water. You can use two separate beakers to hold the two pipets so that
they do not accidently mix. At the end of the lab, students should be
directed to bring HCl beaker with pipet to the teacher for refilling.
Each group will need a small square of sandpaper. Using forceps, students
will gently rub the metal samples over the sandpaper. This is done to
remove oxide coatings which act as protective coatings to the element.
Students will first mix Ca with water and Mg with water.
The Ca will react right away and vigorously. The Mg may react but at a
much reduced rate (if it can be observed). Students should record what
happens and which one is the most vigorous reaction. They should add
only 5-10 drops of water per sample.
For the next row, students will add 5-10 drops of HCl to each of the four
metal samples. Again, they must record what happens and rank the vigor
of the reaction with HCl.
Well plate matrix
Ca + water
Ca + HCl
Mg + water
Mg + HCl
Al + HCl
Zn +HCl
Students will have remaining metal samples which will need to be
disposed. Ca, Mg, and Zn can be reacted with left over HCl and then rinsed
down the drain. The Al can be rinsed with water to remove the HCl and
then thrown in the trash.
Student Handout Below
64
Materials:
Forceps
Ca (calcium), Mg (magnesium), Zn (Zinc), Al (Aluminum), HCl (Hydrochloric acid, in
pipet), and water (in pipet)
Well plate
Piece of sandpaper
Directions:
1. In top row of well plate, using your forceps, place one sample of Ca in the first
well and one sample of Mg in a second well.
2. In the second row of the well plate, using your forceps, place one sample of Ca in
first well, one sample of Mg in second well, one sample of Al in third well, and
one sample of Zn in the forth well. Return to your lab bench.
3. To remind yourself what element is in which well, place a Ca label above the
wells for it as well as a Mg, Al and Zn. (See Figure 1)
4. To the left of the top well plate, put the label water and for the row below, add
the compound HCl. (See Figure 1)
Ca Mg Al Zn
Water
HCl
Figure 1
5. Using your forceps, remove the Ca sample and rub it against the sandpaper. You
may see some pieces come off. This is good. Return it to the well plate.
6. Now to just the Ca, add 5-10 drops of water. Record in your science notebook
what happens.
7. Using your forceps, remove the Mg sample and rub it against the sandpaper. You
should see small scratches on the Mg. Return it to the well and add 5-10 drops of
water. Wait 2 minutes and then record anything that happens. Record even if it
stays the same.
8. Using your forceps, remove the second sample of Ca and rub it against the
sandpaper. Return it to the original well and add 5 drops of HCl. Record in your
notebook what you observe. Be very detailed.
9. Using your forceps, remove the second sample of Mg and rub it against the
sandpaper. You should see tiny scratch marks. Return it to the well and add 5
drops of HCl. Record what you see.
10. Using your forceps, remove the Al sample. Rub it against the sandpaper. If you
see many scratch marks, you are ready to return it to the well. Add 5 drops of
HCl. Record in your notebook anything you see.
65
11. Using your forceps, remove the Zn sample and rub it against the sandpaper.
When you see scratches on the sample, you have done enough. Return sample to
the well and add 5 drops of HCl. Record anything that happens.
12. After 5 minutes, compare all of the wells in the HCl line. Compare amount of
element that remains in well, amount of bubbles in well, amount of bubbling still
occurring. Record all of your comparisons in your notebook.
13. Clean up your station. All of the liquids in the wells may be flushed down the
sink. Make sure that the sink is left running for a minute or two after you have
emptied your well plate. Any remaining metal samples should be returned to
the waste beakers for that metal. Ca in the Ca waste container, Mg, Zn, and Al.
Your teacher will complete the disposal process later.
Questions:
Your group needs to obtain a copy of the periodic table.
1. Which of the four elements are in the same families? Identify them.
2. Which of the four elements are in the same groups/period? Identify them.
3. How would you compare the reactivity of Ca to Mg? In your response refer to
both the water reaction and the HCl reaction.
4. How would you compare the reactivity of Ca to Al?
5. How would you compare the reactivity of Mg to Zn?
6. Classify each element as either: metal, nonmetal or metalloid.
7. Can you create a rule about reactivity for families using your data?
8. Can you create a rule about reactivity for groups/periods using your data?
66
(3) Discussion
Ask student groups to share their observations for each of the reactions.
Record this data in a table (may be electronic or on whiteboard). Refer
students to the periodic table and ask them how they could use the data to
create a rule for elements found in the same period.
Record the rule decided upon by the class.
Repeat this for elements that are found in the same group/family.
What do these rules imply about the periodic table? That it is predictive.
These rules are more period trends. Direct students to record the new
periodic trends in their science notebooks.
Two suggested Science Notebook Frames
In a family, I have observed ___________________. My evidence for this is
_________________.
In a period, I have observed ___________________.
My evidence for this is _________________________________.
Trend
How it changes
in a family
How it changes
in a period
Any exceptions
Mass
Option for early finishers:
http://www.youtube.com/watch?v=0rJmILZ8Psc&feature=related
Video is 8 minutes long and shows physical and chemical properties of
various elements. This video is a good sponge for early finishing students but
is not essential. You can also play this video at anytime during the periodic
table portion when student groups finish early. The video is not intended for
students to watch for content; it is simply to keep students occupied. The
images in the video are nice and they include reactivities. It also is a review
about chemical and physical properties.
(4) Trend Detectives
Start with a review of what is a trend. Return to the trends in reactivity from
the reaction tests and also to the metal, metalloid, and non-metal (i.e. some
trends refer to general sides of the periodic table and not just periods and
columns).
For this activity, students will be in groups of 2-3 students. Each group will
be given a periodic table with one specific property on it. Student groups will
review the property information and determine if they think it is a period,
67
column, or sides of the periodic table trend. It will also be acceptable to
answer that it does not appear to be a trend.
State to students: each group has a periodic table of the elements which
includes just one property: boiling point, melting point, density. The first
thing I wish for you to do is to fold the periodic table so that the 10 short
rows (a region known as the transition metals) are out and the first 2 rows
are next to the last six rows. This is the region to concentrate upon. Your
task is to review the organized data and determine if you see a pattern. When
you do note a pattern, you should record this in your science notebook.
Remember to describe clearly what the trend is. Remember to look by metal
vs. nonmetal, period, and column (family).
Give students some time to review the data. Circulate and prompt student
thinking. For example, for density suggest focusing upon metal versus nonmetal. Another example for melting point and boiling point: “Could a trend be
more like an arch?”
When most students have something written in their science notebook, it is
time for students to share their identified trends along with reasons. Have
each group come forward to present their findings. If you have a document
camera, it would be easier to discuss trends by having the periodic table
displayed.
When groups disagree but have the same property, direct all the students to
the periodic table and review it. Then discuss the evidence provided by both
groups. Sometimes it maybe that one group found part of the trend while
another group found another part and the trends need to be combined.
Possible trends:
Density
The metals to the right have higher densities then those to the left.
Density tends to increase down a column.
Melting Point
Metals tend to have higher melting points that non-metals.
Across a period, the melting points increase and then begin to
decrease.
All but one negative value is found on the right-hand side of the
periodic table.
In columns 1, 2 and 3 the melting points decrease as you go from the
top to the bottom.
Boiling Point
In columns 1, 2, 3, and 4 the boiling point decreases as you go from
the top to the bottom.
68
Metals tend to have higher boiling points than non-metals.
Boiling points from left to right start to increase and then in the
middle decrease again.
Some questions to ask after some general trends are determined. What does it
mean for the state of matter if it is boiling? Is it both a liquid and a gas because both
states of matter may exist at that temperature. If the temperature continues to rise,
all of it will be a gas.
Based upon the melting points and boiling points for non-metals, what state of
matter do you think the majority would be if they were in this class room? (gas)
In your science notebook, respond to the following questions:
What does it mean to be a general trend?
How can the periodic table be useful for a chemist?
Below you will find the three periodic tables for activity section 4
69
Periodic Table of the
Elements
Density
1A
8A
http://chemistry.about.com
2A
3A 4A 5A 6A 7A
3B 4B 5B 6B 7B ┌───── 8B ─────┐ 1B 2B
*** Elements > 104 exist only for very short half-lifes and the data is unknown.***
Lanthanides
Actinides
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
La
Ce
Pr
Nd
Pm
Sm
Eu
Gd
Tb
Dy
Ho
Er
Tm
Yb
Lu
6.15
6.77
6.77
7.01
7.26
7.52
5.24
7.90
8.23
8.55
8.80
9.07
9.32
6.90
9.84
103
89
90
91
92
93
94
95
96
97
98
99
100
101
102
Ac
Th
Pa
U
Np
Pu
Am
Cm
Bk
Cf
Es
Fm
Md
No
Lr
10.0
11.7
15.4
19.1
20.2
19.7
13.6
13.5
14.8
unknown
unknown
unknown
unknown
unknown
unknown
70
Periodic Table of the
Elements
Melting Point
1A
8A
http://chemistry.about.com
3B 4B 5B 6B 7B ┌───── 8B ─────┐ 1B 2B
*** Elements > 104 exist only for very short half-lifes and the data is unknown.***
Lanthanides
Actinides
57
58
La
Ce
920
799
59
60
61
62
63
64
65
66
67
Pr
Nd
Pm
Sm
Eu
Gd
Tb
Dy
Ho
931
1016
1042
1072
822
1313
1356
1412
1472
68
69
70
71
Er
Tm
Yb
Lu
1529
1545
824
1663
103
89
90
91
92
93
94
95
96
97
98
99
100
101
102
Ac
Th
Pa
U
Np
Pu
Am
Cm
Bk
Cf
Es
Fm
Md
No
Lr
1050
1750
1572
1135
664
640
1176
1345
996
900
860
1527
827
unknown
unknown
71
Periodic Table of the
Elements
Boiling Point
1A
8A
http://chemistry.about.com
3B 4B 5B 6B 7B ┌───── 8B ─────┐ 1B 2B
*** Elements > 104 exist only for very short half-lifes and the data is unknown.***
Lanthanides
Actinides
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
La
Ce
Pr
Nd
Pm
Sm
Eu
Gd
Tb
Dy
Ho
Er
Tm
Yb
Lu
3464
3443
3520
3074
3000
1794
1596
3273
3230
2567
2700
2868
1950
1196
3402
103
89
90
91
92
93
94
95
96
97
98
99
100
101
102
Ac
Th
Pa
U
Np
Pu
Am
Cm
Bk
Cf
Es
Fm
Md
No
Lr
3198
4788
unknown
4131
unknown
3228
2011
unknown
unknown
unknown
unknown
unknown
unknown
unknown
unknown
72
Tabla Periódica de los
Elementos
1A
A
Lantánido
Actínido
Alcalino
8A
http://chemistry.about.com
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
La
Ce
Pr
Nd
Pm
Sm
Eu
Gd
Tb
Dy
Ho
Er
Tm
Yb
Lu
138.905
47
140.116
144.242
[145]
150.36
151.964
157.25
158.925
35
162.500
164.930
32
167.259
168.934
21
173.054
174.966
8
Lantano
Cerio
Neodimi
o
Prometio
Samario
Europio
Gadolini
o
Terbio
Disprosi
o
Holmio
Erbio
Tulio
Iterbio
Lutecio
103
89
90
Ac
Th
[227]
232.038
06
Actinio
Torio
Alcalinotérreo
140.907
65
Praseodi
mio
91
92
93
94
95
96
97
98
99
100
101
102
Pa
U
Np
Pu
Am
Cm
Bk
Cf
Es
Fm
Md
No
Lr
238.028
91
[237]
[244]
[243]
[247]
[247]
[251]
[252]
[257]
[258]
[259]
[262]
Uranio
Neptunio
Plutonio
Americio
Curio
Berkelio
Californi
o
Einsteni
o
Fermio
Mendele
vio
Nobelio
231.035
88
Protactin
io
Metales del
bloque p
Halógeno
Gas noble
73
No metal
Tierras raras
Metaloides
Laurenci
o
Metal de
transición
8. Modeling of the PT
Learning Targets:
I can explain that the type of model you use is based upon the model’s
purpose.
I can explain how models are predictive.
Focus Question:
How does the purpose of a model effect its development?
Key Vocabulary:
Sequence of Experiences
1.
Reading about Mendeleyev
30 min
2.
Discussion of how is the Periodic Table a model?
30 min
Materials:
How is the PT a model? What is it modeling?
How to read a reaction from the PT modeling
(1) Putting Things in Order
Putting Things in Order from The Story of Science: Newton at the Center pages
298 to 308
Students should be provided copies of the reading. Each student will be
responsible for reading the passage and then answering the reflective
questions.
Before Reading:


Have students read the quotes on pg. 298.
Turn to a partner and discuss, “Why is the Periodic Table so important
to the study of chemistry?
74

Scan the text and discuss the layout. This is a narrative. What are
features present in a narrative? How might a narrative be organized
(text structure)? What might the text structure help you understand
about the author’s purpose?
During Reading:






Create a rough timeline of Mendeleyev’s life as you read the passage.
Identify some key events and mentors of Mendeleyev.
Note some of the ways Mendeleyev tried to organize the known
elements.
Identify the trends that emerged from his organization.
Identify the key benefits of the Periodic Table.
Is the Periodic Table complete? Would you expect changes to it in the
future? Why or why not?
After Reading:
Discuss what has been learned and move to the next part of the discussion
which is: Is the Periodic Table a Model?
(2) How is the Periodic Table a Model?
From prior lessons the discussion of models and chemistry surfaced over
and over again. Now it is time to focus on the periodic table.
What are some of the criteria for being a model? Predictive, has
limitations, not a replica, a simplification, etc.
What are some examples of models discussed so far in this unit? The
periodic table, the model drawings of the water expander, the particle
model, Rutherford’s model, Bohr model
What can a model do for a scientist? It communicates the scientists idea
or concept to others so they many more fully understand. It can be used
by other scientists to build upon it and modify it based upon new
information.
Would you classify the periodic table as a model? Why or why not? Have
students record their reasoning and then discuss with a student sitting
next to them.
Next, return to their ‘What is a Model’ Probe (stapled into their
notebooks). Ask students to make any revisions to the items they have
75
selected. Next, discuss again what makes a model and how do we define a
model in science.
Pass out Frayer Model for the term ‘Model.’ Work with students to
identify characteristics of a model and to refine/develop a more inclusive
definition of a model. They should write in pencil.
Ask students to record the examples of models from this unit of study.
Then ask students to give non-examples of models.
76
1. Provide a strong reason for the need for chemistry to be ‘standarzied.’
Characteristics
Definition
What was the state of chemistry at the time.
Examples
Model
77
Non-Examples
References
Flinn Scientific. (2003). Atomic Target Practice. Catalog number AP6496
Hakim, J. (2005)Putting Things in Order, ch 29, p. 298-308 in The Story of Science:
Newton at the Center. Washington, DC: Smithsonian Books.
Helmenstine, T. (2010) Periodic Table of the Elements: Boiling Point, Density, and
Melting Point. Retrieved from: http://chemistry.about.com
Keeley, P. (2008). Science Formative Assessment: 75 Practical Strategies for Linking
Assessment, Instruction, and Learning. Thousand Oaks: Joint Publication with
Corwin Press and the National Science Teachers Association.
Keeley, P., Eberle, F., Farrin, L., & Olliver, L. (2005). Uncovering Student Ideas in
Science, Vol. 1: 25 formative assessment probes. Arlington, VA: National
Science Teachers Association Press.
Keeley, P., & Tugel, J. (2009). Uncovering Student Ideas in Science, Vol. 4: 25 New
Formative Assessment Probes. Arlington, VA: National Science Teachers
Association Press.
Kosasih. (2008, January 8). Nucleus of an Atom. Video Retrieved from:
http://www.youtube.com/watch?v=Q8RuO2ekNGw
Kosasih. (2008, January 8). Cathode Ray Experiment. Video Retrieved from:
http://www.youtube.com/watch?v=XU8nMKkzbT8&feature=related
Miami Science Museum. (1997). The Phantom’s Portrait Parlor Paper Cutting.
Retrieved from:
http://www.miamisci.org/af/sln/phantom/papercutting.html
Periodictabledotcom. (2009, September 24). Periodic Table Animation of All the
Elements. Video Retrieved from:
http://www.youtube.com/watch?v=0rJmILZ8Psc&feature=related
PhET Team. (2011). Build an Atom. Retrieved from:
http://phet.colorado.edu/en/simulation/build-an-atom#softwarerequirements
Stalldog. (2009, January 20). Rutherford. Video Retrieved from:
http://www.youtube.com/watch?v=bSEOOMs5VNU
Stalldog. (2009, January 20). Bohr. Video Retrieved from:
http://www.youtube.com/watch?v=wCCz20JOXXk&NR=1
78
Appendix
Template for learning target and ‘What did I learn?’ and ‘What did I do?’
Target:
What did I learn?
What did I do?
79
Targets- Atoms
I am
confident
I can identify the parts of an atom which made
up its structure. (nucleus, electron cloud,
neutron, electron, proton)
I can distinguish the parts of an atom based upon
mass and charge. (proton, electron, neutron)
I can demonstrate, in words and pictures, how
the size of an atom compares to a visible object.
I know what holds an atom together.
80
I am sort of
confident
I am not
confident
Plan to improve
confidence
Targets- Periodic Table
I am
confident
I can define an element. (single type of atom)
I can classify atoms into element categories.
I can classify substances using reactivities into
like groups (families).
I can describe patterns from periods and families
from the periodic table.
I can predict missing elements based upon
existing pattern.
I can identify chemical trends using atomic
numbers and data in tables/graphs
(flammability, and reactivity).
I can identify physical trends using atomic
numbers and data in tables/graphs (density,
boiling point, and solubility).
I can identify groups of elements with similar
properties (metals, non-metals and nonreactive).
I can use reactivities to classify substances into
like reactivity groups.
I can rank order reactivity based upon data
patterns.
81
I am sort of
confident
I am not
confident
Plan to improve
confidence
Targets- Biogeochemical Cycles
I am
confident
I can compare the elements essential for life to
those found in the Earth’s crust, oceans, and
atmosphere.
I can make inferences about the source of these
elements.
I can identify processes that produce and consume
organic forms of carbon molecules and CO2
molecules.
I can identify processes that produce and consume
organic forms of carbon molecules and CO2
molecules.
I can describe how different types of plants store
Carbon.
I can explain how a plant uses CO2.
I can explain a plant’s role in carbon cycling.
I can describe how matter and energy are
transformed in a food chain and ecosystems.
I can describe how matter and energy are
transformed during decomposition.
I can describe interactions between the bio- and
atmosphere in terms of carbon cycling.
I can explain how land use decisions can cause
imbalance in the amount of Carbon released or
stored.
I can describe how different types of soils store
Carbon.
I can explain how different variables affect
decomposition by soil organisms.
82
I am sort of
confident
I am not
confident
Plan to improve
confidence
Targets- Conservation of Matter
I am
confident
I am sort of
confident
I am not
confident
Plan to improve
confidence
I am
confident
I am sort of
confident
I am not
confident
Plan to improve
confidence
I can modify the definition of matter (to include
the concepts of atom and element).
I can explain the relationship between atoms
and the conservation of matter.
I can use the existence of atoms to demonstrate
the conservation of matter.
I can interpret evidence which supports the
conservation of matter.
Targets- Models
I can explain how models are predictive.
I can use a model to explain the effect of
increasing and decreasing scale (in 2-D and 3-D).
I can explain how models are different from
reality.
I can distinguish between different forms of
models.
I can analyze multiple, basic atomic structure
models for advantages and limitations.
I can identify the form of model to use.
I can explain that the type of model you use is
based upon the model’s purpose.
83