E 3.1.1.2. Chemistry Sciences: A. Building Blocks of Matter
Lesson Plan: Characteristic Properties
Abstract
Students will learn about characteristic properties by first conducting an investigation
to determine the relative density of water, oil, rubbing alcohol, and a green bead. Then,
they will observe how quickly a green bead moves through test tubes filled with water,
oil, and corn syrup to determine which liquids have higher viscosity. Finally, they will use
appropriate tools to separate iron filings from a soil sample, dissolve salt, and separate sand.
Time: 30 Minutes
Objectives: Chemistry Sciences: A. Building Blocks of Matter
1. The learner will conclude there are more than 100 known elements
that combine in a multitude of ways to produce compounds, which account for all living
and non-living substances.
2. The learner will demonstrate that atoms combine to form molecules and molecules
formed from different atoms combine to form compounds.
3. The learner will recognize a substance has characteristics, such as density, viscosity,
boiling point, and solubility, all of which are independent of the amount of the sample.
Lesson Plan
Appendices
Characteristic Properties
Objectives Met
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E 3.1.1.2. Chemistry Sciences: A. Building Blocks of Matter
Lesson Plan: Characteristic Properties
Instructor Materials
• 1 Foam brick that looks like foam
• 1 Foam brick that looks like a brick
Student Materials
Density (Per team of 4 students)
• 1 - 100mL graduated cylinder with 20 mL of
vegetable oil
• 1 - 100mL graduated cylinder for measuring
• Funnel
• 1 Cup of water, dyed blue
• 1 Cup of 91% rubbing alcohol, dyed green
• 1 Green bead
• 1 Plastic tub lined with a trash bag
• 2 Paper towels
• Safety goggles (per student)
• Gloves (per student)
• Station cards
Viscosity (Per student)
• 1 Test tube with cooking oil and a green bead in it,
labeled “A”
• 1 Test tube with water and a green bead in it,
labeled “B”
• 1 Test tube with corn syrup and a green bead in it,
labeled “C”
• Test tube holder
• Safety goggles (per student)
• Gloves (per student)
• Station cards
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E 3.1.1.2. Chemistry Sciences: A. Building Blocks of Matter
Lesson Plan: Characteristic Properties
Solubility (Per team of 4 students)
• 2 Soil samples with a mixture of sand, salt, and iron
filings – one larger than the other
• Coffee filter
• 2 Magnets
• 4 oz cup with about 1 tsp of water
• 4 oz cup for iron filings
• 12 oz cup (empty)
• Safety goggles (per student)
• Gloves (per student)
• Station cards
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E 3.1.1.2. Chemistry Sciences: A. Building Blocks of Matter
Lesson Plan: Characteristic Properties
Instructor Background Information:
Key Vocabulary
Characteristic
Properties—A
characteristic property
is a chemical or physical
property that helps identify
and classify substances. The
characteristic properties
of a substance are always
the same whether the
sample you are observing
is large or small. Examples
of characteristic properties
include freezing/melting
point, boiling/condensing
point, density, magnetism,
and solubility.
Density—The amount
of mass per unit volume.
Something that is more
tightly packed is denser
than something that has
more space between the
molecules.
Solubility —The ability of a
substance to dissolve. The
quantity of a substance that
may be dissolved in a given
amount of solvent.
Solute—A substance
dissolved in a solution.
For solutions of fluids, the
solvent is present in greater
amount than the solute.
Solvent—The component
of a solution that is present
in the greatest amount. It is
the substance in which the
solute is dissolved.
Viscosity—The property of
a fluid that resists the force
tending to cause the fluid
to flow.
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E 3.1.1.2. Chemistry Sciences: A. Building Blocks of Matter
Lesson Plan: Characteristic Properties
Density
Density is a relationship of mass to volume expressed in the
equation
Density =
mass (g)
volume (mL)
In other words, density is defined as the amount of mass per unit
volume. Something that is more tightly packed is denser than
something that has more space between the molecules.
At the atomic level, the higher the number of protons and
neutrons in the atom, the greater the atomic mass, which can be
observed on the Periodic Table of Elements. Further, the strength
of the atomic bonds can play a role in density as stronger bonds
result in more atoms crowded together.
The same holds true with molecular bonds. More tightly bonded
molecules mean less space between them, which typically results
in high density. Metals are a good example of tightly bonded
atoms.
Density can also change as a result of variations in pressure and
temperature; therefore, it is said to be a dynamic property. The
best way to understand this is to think in terms of gases. If a set
amount of a gas is moved from a small container to a larger one,
the gas will tend to spread out. The smaller container exerts
a higher level of pressure, packing the gas molecules closer
together; when that pressure is no longer acting on the gas, the
molecules will spread out, thus reducing the density.
Temperature also can play a role as high temperatures increase
kinetic energy. In turn, this causes molecules to spread out, thus
affecting density.
An important consideration when teaching density is to
emphasize the difference between mass and weight. Weight is
relative to gravitational pull while mass is a constant. Because
density is a relationship of mass to volume expressed in the
equation Density = mass (g)/volume (mL), this distinction must
be clear.
Weight is not a reliable means of determining density and neither
is size. Sometimes students may wrongly conclude that larger
objects automatically have greater density or that an object that
sinks in one type of liquid will automatically sink in all liquids.
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E 3.1.1.2. Chemistry Sciences: A. Building Blocks of Matter
Lesson Plan: Characteristic Properties
Viscosity
Viscosity is the property of a fluid’s resistance to flow. Viscosity is
described as the ratio of shearing stress to the velocity gradient.
Shearing stress results from the force of one side of a surface
pressing against the side of another surface. When a fluid is
moving, the outside layer of the fluid will move at the same
velocity as the movement, if any, of the surface it is pressing
against.
If it is a pipe that is stationary, the outer layer of the fluid inside
will not be moving while the inner layers will be moving. The
difference in movement between the outer and inner layers is
called the velocity gradient. If there is little difference between
the layers, the flow is called a laminar flow.
The simplest way to measure viscosity is to put a known quantity
of fluid into a funnel and measure how long it takes to flow
through. This is called kinematic viscosity and is actually a
measurement of how a fluid resists flow under the influence of
gravity.
Solubility
Solubility is the ability of a substance to dissolve. Usually, we
think in terms of dissolving something in water; however,
different solvents can affect solubility. Matter can be classified
based on how the characteristic property of its solubility is
affected in different solvents. The substance (chemical) being
dissolved is called a solute, and the liquid it is being dissolved in
is called a solvent.
Solubility is expressed in quantitative terms. For example, a
solute is stirred into a known amount of solvent, (100mL). When
more than 0.1g of the solute dissolves (disappears), it is said to
be soluble. If less than 0.1g of the solute dissolves, it is said to
be either insoluble or sparingly soluble. When a substance is
miscible, it is understood to be soluble without limits. Immiscible
is synonymous with insoluble.
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E 3.1.1.2. Chemistry Sciences: A. Building Blocks of Matter
Lesson Plan: Characteristic Properties
Instructor Preparation:
Set Up
üü Collect the necessary supplies for each group of four
students.
Caution students that they should
not drink any solutions utilized as
part of an investigation.
Caution students that rubbing
alcohol can be harmful if misused.
Avoid contact with skin.
While working with the iron filings,
warn the students to keep fingers
away from eyes.
Density
• 1-100mL graduated cylinder with 20 mL of
vegetable oil
• 1 cup of water tinted with blue food coloring
• 1 cup of 91% rubbing alcohol tinted with green food
coloring
• 1 plastic tub, lined with a trash bag and two paper
towels
Viscosity
• 4 test tubes marked “Sample A” with cooking oil and
a green bead in each
• 4 test tubes marked “Sample B” with water and a
green bead in each
• 4 test tubes marked “Sample C” with light corn syrup
and a green bead in each
Solubility
• 2 - 6oz clear plastic cups labeled “Water,” 1
tablespoon of water in each
• 2 - 6oz clear plastic cups labeled “Used Iron Filings”
• 1 plastic bag with ¼ cup of sand, 1 tsp. salt, and ¼
tsp. iron filings
• 1 plastic bag with 2 teaspoons sand, ½ tsp. salt, and
¼ tsp. iron filings
• 2 magnets
• 2 basket-type coffee filters
Activity Preparation
üü Density—At each station, place one empty graduated
cylinder, one graduated cylinder with vegetable oil, a funnel,
the cup of blue water, the cup of green rubbing alcohol, and
a green bead on top of the paper towels. Also place a pair
of gloves and goggles for each student. Put the lined plastic
container on one end of the table.
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E 3.1.1.2. Chemistry Sciences: A. Building Blocks of Matter
Lesson Plan: Characteristic Properties
üü Viscosity—At the same station where the density equipment
is placed, put the test tubes in a test tube holder.
üü Solubility—At each station, place two 12 oz plastic cups, a
coffee filter with the larger soil sample, a coffee filter with
the smaller soil sample, the cups with water (students work
in pairs), and a pair gloves and goggles for each student. Set
magnets and cups for used iron filings to the side.
8
E 3.1.1.2. Chemistry Sciences: A. Building Blocks of Matter
Lesson Plan: Characteristic Properties
Lesson:
Introduction: 5 minutes
1. Hold up a glass of water.
Ask: What is this? (A glass of water.)
Ask: How do you know? (It’s clear liquid in a glass.)
Ask: How do you know for sure it’s water? What else could it
be? (Vinegar, rubbing alcohol, acid.)
We would need to test its characteristic properties to
determine for sure that it is actually water and not something
else.
2. Ask: Does anyone know what a characteristic property
is? (Allow students a moment to offer their ideas. Explain,
characteristic properties are physical or chemical properties
that scientist use to identify unknown substances. They remain
the same regardless of the amount or size of the sample. Some
characteristic properties of this glass of water would be its
density and viscosity.)
3. Ask: Can someone explain what density means? (Density is
the amount of mass of an object in relation to the space it takes
up.)
Help the class get a visual idea of density by giving an
example of density such as a fully packed classroom
compared to a nearly empty one. Then, explain that density
can be different based on the state of matter.
4. Explain to the class that they will be conducting an
investigation to observe the density of three unknown
liquids. Point out the graduated cylinders, so the students are
familiar with what equipment they will be using. Remind the
class to carefully read the instructions on their station cards.
5. Ask: Does anyone know what viscosity means? (Viscosity is
how fast a fluid flows. Viscosity is how much a fluid resists
flow.)
Density is taught as Station 1A,
while viscosity is taught as Station
1B. The stations are combined
because each activity only takes
five minutes. The total station time
needs to be 10 minutes to match
the Solubility station.
Low viscosity means the fluid flows very fast; high viscosity
means the fluid flows very slowly. Point out the test tubes at
the station and remind students to read their station cards.
6. Solubility is taught as its own station.
Ask: What is the definition of solubility? (Solubility is a
measure of a substance’s ability to dissolve.)
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E 3.1.1.2. Chemistry Sciences: A. Building Blocks of Matter
Lesson Plan: Characteristic Properties
7. Explain to the class that they will be working with soil
samples and will need to read their station cards to properly
separate the substances in the soil sample.
Stations: 10 Minutes each station
Station 1A (Density)—5 Minutes
Figure 1: Station 1A—Density Set-up
Optional: To simplify student
tasks, you can assign each group
member a number, one through
four, to coordinate with the steps
of these stations. If you choose
not to assign numbers, you should
ensure that each member has an
opportunity to participate.
8. One student picks up the graduated cylinder with the yellow
liquid in it.
9. Using the funnel, another student measures 10 mL of blue
liquid into the empty graduated cylinder and then hands it
back to the first student who will pour it on top of the yellow
liquid.
10. Using the funnel, a third group member measures 30 mL of
green liquid into the empty graduated cylinder and then
hands it back to the first student to pour it on top of the
yellow liquid.
11. The students should observe how the liquids separate into
three layers, as seen in Figure 2.
12. The final group member should then drop the green bead
into the graduated cylinder. Everyone should observe where
it goes.
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E 3.1.1.2. Chemistry Sciences: A. Building Blocks of Matter
Lesson Plan: Characteristic Properties
Figure 2: Density Graduated Cylinder
13. The teams will analyze and report the results by answering
three questions and completing the table in their activity
logs. Students will use the table on the station card to identify
the liquids in the graduated cylinder.
To ease the transition from station
to station, it would help to have
multiple sets of equipment for
students to use.
14. Students empty the graduated cylinder with the stacked
liquids into the plastic bin and retrieve the green bead for the
next crew.
Station 1B (Viscosity)­—5 Minutes
Figure 3: Station 1B - Viscosity Set-up
15. Each person at the table should take one of each of the test
tubes (labeled “Sample A,” “Sample B,” and “Sample C”) and tip
them to observe how the liquid flows in each test tube.
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E 3.1.1.2. Chemistry Sciences: A. Building Blocks of Matter
Lesson Plan: Characteristic Properties
16. Next, they should identify if the viscosity of each is either
high or low and complete the table in their activity log.
Station 2 (Solubility)­—10 Minutes
17. Students should read the following scenario from their
station card:
Optional Scenario: Your robot collected two different
samples from the ground near the volcanic eruption. Your
job is to determine what is in the soil and make sure that it is
not contaminated. From researching, you know that the soil
should contain iron, sand, and salt. You will need to test the two
samples to find out if they contain these substances. Work in
pairs.
18. Students should then follow the directions on their station
card to complete a table. (This is their plan for separating the
soil samples).
19. Once they have completed the table, the pairs will empty
their soil sample into the coffee filter. Give each pair of
students a magnet and a cup labeled “Used Iron Filings.”
Allow them time to remove the iron filings and scrape them
off the magnet and into the cup.
20. Students should then hold their soil sample (with iron filings
removed) over the 12 oz plastic cup and pour water over it to
dissolve the salt.
21. Once they have completed the activity, students should
answer the questions in their activity logs to report their
observations.
Figure 4: Station 2—Solubility
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E 3.1.1.2. Chemistry Sciences: A. Building Blocks of Matter
Lesson Plan: Characteristic Properties
Conclusion: 5 Minutes
22. Begin with a discussion of characteristic properties and
explain to the class that characteristic properties help us
identify substances because they do not change. Density,
viscosity, and solubility are all considered characteristic
properties.
Density and Viscosity Station
23. Hold up the two “bricks.”
Ask: Which of these two materials is more dense, a foam brick
or a real brick? What is the difference? (A real brick would have
more density. They are different because the real brick has more
mass than the foam brick, but it takes up the same amount of
space. Some students may answer that it weighs more. Use this
as a teachable moment to discuss weight and mass.)
Ask: Which liquid had the highest density? How do you
know? (Student answers should include that water had the
highest density because it went to the bottom of the graduated
cylinder, and its density was 1.00 gm/mL, which was the highest
number on the table.)
Strategic Questions:
Why did the rubbing
alcohol stay on top?
(It had the lowest density.)
Will changing the amounts
of any of the liquids affect
their density? Why or why
not?
(No, because characteristic
properties, such as density,
will not change regardless
of the amount of the
substance.)
24. Identify the yellow liquid as cooking oil and the green liquid
as rubbing alcohol.
Ask: Did the amount of each liquid make a difference to
how they stacked up in the graduated cylinder? (No, because
the amount of a substance does not change its characteristic
properties.)
Ask: Why did the water go through the oil to the bottom,
but the rubbing alcohol didn’t? What caused this difference?
(The density of the oil is less than the density of the water,
which means the molecules are not as tightly bonded, leaving
space for the water to move through it. On the other hand, the
molecules in the rubbing alcohol are spaced farther apart, so it
could not move through the oil.)
Ask: What about the bead; where did it end up? Why didn’t
it go all the way to the bottom? What can we tell about its
density? (The bead floated between the water and the oil.
Its density is less than water but greater than the oil. We can
estimate its density around 0.95 g/mL.)
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E 3.1.1.2. Chemistry Sciences: A. Building Blocks of Matter
Lesson Plan: Characteristic Properties
Strategic Questions:
A liquid that hardly
budges has which
viscosity, high or low?
(High.)
Can you think of some
liquids with a high
viscosity?
(Honey, pancake syrup,
molasses.)
25. Move onto a discussion of viscosity and review that liquids
that do not flow easily have a high viscosity, while liquids
with low viscosity flow quickly.
Ask: What might you put on your pancakes that does not
flow easily? (Syrup.)
Ask: What liquid with a low viscosity might you drink? (Milk,
orange juice, water.)
26. Then, go through the test tube samples and ask the class to
identify the viscosity of each liquid.
• Sample A can be either a high or low viscosity. However,
because liquids are only classified in this activity as either
having high or low viscosity, medium is not an option.
• Sample B is a low viscosity. The students can observe the
bead moves very quickly through the liquid.
• Sample C is a high viscosity. The students can observe the
bead moves very slowly through the liquid.
Solubility
Strategic Questions:
Does the amount or size
of a sample affect its
solubility?
(No, because characteristic
properties are not affected
by the amount or size of the
substance.)
27. Review the definition of solubility (a substance’s ability to
dissolve), and remind the class that characteristic properties
do not change regardless of the amount of the substance.
28. Ask the class if they were successful in separating the three
substances. Then, ask if the amount of the sample made a
difference to their success?
Explain that the characteristic properties of each substance
wouldn’t change even if we had a dump truck full of mixed
up sand, salt, and iron filings. With the correct tools, we could
still be successful. We could use a magnet to separate the iron
filling from the sand, and we could still rinse the salt out with
water.
14
Characteristic Properties Assessment
Suggested Final Assessment Questions
1. How might understanding characteristic properties help
scientists identify unknown substances?
2. Does the amount of a substance affect its density? Why or
why not?
3. If a liquid flows slowly, does it have a high or low viscosity?
4. Which is not an example of a characteristic property?
a. Density
b. Viscosity
c. Size
d. Solubility
15
Characteristic Properties Assessment
Suggested Final Assessment Questions
Application
1. How might understanding characteristic properties help
scientists identify unknown substances?
Characteristic properties do not change and are, therefore, very
helpful to separate and identify substances.
Knowledge
2. Does the amount of a substance affect its density? Why or
why not?
No, because density is a characteristic property and is
independent of the size of the sample.
Knowledge
3. If a liquid flows slowly, does it have a high or low viscosity?
High.
Comprehension
4. Which is not an example of a characteristic property?
a. Density
b. Viscosity
c. Size
d. Solubility
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Activity Log
Characteristic Properties
Station #1: What is density & viscosity?
The density of a substance describes the mass of the substance in the amount of
space it takes up. Viscosity is determined by how much a liquid resists flow. Liquids
that do not flow easily have high viscosity. Liquids that flow quickly have low
viscosity.
After pouring the liquids into the graduated cylinder...
1. Which liquid has the highest density?
o Green
o Yellow
o Blue
2. Which liquid has the lowest density?
o Green
o Yellow
o Blue
3. The density of the bead is between which two liquids?
o Green
o Yellow
Density of Liquids (1A)
Color
Identity
Density
(g/mL)
o Blue
Viscosity of Liquids (1B)
Sample
Blue
A
Yellow
B
Green
C
Viscosity
(high, low)
Characteristic Properties
Activity Log
Station #2: What is solubility?
Your plan for separating the three substances:
Step
Substance
1
Iron
2
Salt
3
Sand
Characteristic Properties
Tool
1. Were you successful in separating the three substances? Why or why not?
__________________________________________________________________
__________________________________________________________________
2. Did the amount of iron, sand, or salt affect your ability to separate them?
Why do you think this is?
__________________________________________________________________
__________________________________________________________________
3. What substance is in the water? _______________________________________
Can you see the substance? __________________________________________
Why or why not? ___________________________________________________
__________________________________________________________________
Activity Log
Characteristic Properties
Station #1: What is density & viscosity?
The density of a substance describes the mass of the substance in the amount of
space it takes up. Viscosity is determined by how much a liquid resists flow. Liquids
that do not flow easily have high viscosity. Liquids that flow quickly have low
viscosity.
After pouring the liquids into the graduated cylinder...
1. Which liquid has the highest density?
o Green
o Yellow
R Blue
2. Which liquid has the lowest density?
R Green
o Yellow
o Blue
3. The density of the bead is between which two liquids?
o Green
R Yellow
R Blue
Density of Liquids (1A)
Viscosity of Liquids (1B)
Color
Identity
Density
(g/mL)
Sample
Viscosity
(high, low)
Blue
Water
1.00
A
Either high or low
Yellow
Vegetable Oil
0.91
B
Low
Green
Rubbing Alcohol
0.78
C
High
Characteristic Properties
Activity Log
Station #2: What is solubility?
Your plan for separating the three substances:
Step
Substance
Characteristic Properties
Tool
1
Iron
Magnetic
Magnet
2
Salt
Dissolves
Water
3
Sand
Doesn’t Dissolve
Filter Paper
1. Were you successful in separating the three substances? Why or why not?
__Yes, because we used the correct tools._______________________________________
__________________________________________________________________
2. Did the amount of iron, sand, or salt affect your ability to separate them?
Why do you think this is?
__No, because characteristic properties stay the same regardless of the size of the sample. _____
__________________________________________________________________
3. What substance is in the water? __Salt__________________________________
Can you see the substance? __No______________________________________
Why or why not? __Because, it dissolves into the solvent._________________________
__________________________________________________________________
E 3.1.1.2. Chemistry Sciences: A. Building Blocks of Matter
Lesson Plan: Characteristic Properties
References:
Characteristic Property. (n.d.). Wikipedia. Retrieved from http://en.wikipedia.org/wiki/
Characteristic_property
Elert, G. (2012). The Physics Hypertextbook. Retrieved from (http://physics.info/viscosity/
Grotzer, Tina et al. (2005). Understandings of Consequence Project: Causal Patterns in Density
Phenomena. Retrieved from http://www.pz.harvard.edu/ucp/curriculum/density/i_challenges.
htm
Ophart, C.E. (2003) What is Density? Retrieved from http://www.elmhurst.edu/~chm/
vchembook/120Adensity.html
Pressure and Density. (2012). Retrieved from http://www.kidsgeo.com/geography-for-kids/0084pressure-and-density.php
Rogers, E., Stofall, I., Jones, L., Chabay, R., Kean, E., Smith, S. (2000) Fundamentals of Chemistry.
Retrieved from http://www.chem.wisc.edu/deptfiles/genchem/sstutorial/Text11/Tx112/tx112.
html
Related Materials and Educational Resources:
Fake foam brick
• http://www.amazon.com
Iron filings
• www.sanjosescientific.com (SKU: 4942-35A Recommended)
21
Station #1A: Density
Person
Person
Person
1
2
3
Pick up the
graduated
cylinder with
the yellow
liquid.
Using the
funnel,
measure 10
mL of blue
liquid in
the other
cylinder and
give it to
Person #1 to
pour on top
of yellow
liquid.
Using the
funnel,
measure 10
mL of green
liquid in
the other
cylinder and
give it to
Person #1 to
pour on top
of yellow
liquid.
STOP
Observe
Person
Observe how
the liquids
stack in the
graduated
cylinder.
Drop the
green bead
into the
graduated
cylinder.
Observe
where it goes.
4
5
ANSWER questions 1-3 in your Activity Log.
6
Identify the liquids using the table below. Fill in the table in your Activity Log.
Density of Liquids:
Rubbing Alcohol:
.78g/ mL
Vegetable Oil:
.91g/mL
7
Water:1.00g/mL
Pour the entire contents of the graduated cylinder into the waste container. Wipe
up any spills with paper towels. Leave all items on the table as you found them.
Station #1B: Viscosity
1
Each crew member take a test tube labeled “Sample A.”
2
Tip the test tube back and forth.
3
Observe how the liquid flows in the test tube.
4
Repeat steps 1-3 with the test tubes labeled “Sample B” and
“Sample C.”
5
Identify the viscosity of each sample as either high or low.
6
Complete the table in your Activity Log.
Station #2: Characteristic Properties (Solubility)
Your robot collected two different samples from the ground near the volcanic eruption.
Your job is to determine what is in the soil and make sure that it is not contaminated. From
researching, you know that the soil should contain iron, sand, and salt. You will need to test
the two samples for these substances. Work in pairs.
Your plan:
1
In your Activity Log, write your plan for testing and
separating the three substances. The characteristic
properties and tools you might use are listed in the blue box
below.
CHARACTERISTIC PROPERTIES
Dissolves (soluble)
Magnetic
Doesn’t dissolve (insoluble)
Carry out plan:
2
TOOLS
Water
Magnet
Filter Paper
a. Pour the soil onto the filter paper.
b. Allow each crew member to remove a small amount
of the iron and put them in the cup labeled “used iron
filings.” Take turns until all iron is removed.
c. Place the filter over the red cup and hold onto the filter
very tightly.
d. Carefully pour water over the filter.
e. OBSERVE what happens.
f. Throw the filter paper in the trash.
3
ANSWER questions 1 - 3 in your Activity Log.