This lesson was created as a part of the SMART website and is hosted by the Illinois Institute of Technology
This
lesson is intended for grades 3-5, although it can easily be adapted
for lower
or higher grades.
1. Students will be able to distinguish similarities and differences of matter.
2.
Students will be able to recognize that different states of
matter may
appear in one substance
|
Materials: Shaving cream Paper towels Penny Magnifying glass |
Tablespoon Cornstarch Water Plastic Spoon Worksheet |
Strategy:
Students
will be grouped into fours. Each member will actively participate
and
assume one of the following roles:
The
teacher should review the properties of each of the states of matter before
the students begin the experiment. The
getter collects all the materials
needed for the activity, which include shaving cream, 2 paper towels,
and a
penny. The reader reads
the directions, while the starter squirts a small
amount of shaving cream onto one of the
paper towels. The students are to
look at the shaving cream and decide, as a group, whether or not
‘shaving
cream’ is a solid, liquid, or a gas. The
recorder meanwhile writes down their
responses.
Activity
2:
In
this activity, students will create another weird state of matter by
mixing 2
tablespoons of cornstarch with 1 tablespoon of water.
(The starter does the mixing.)
Each
member will stir the substance quickly and notice that the material
acts more
like a solid, but when they mix it slowly, it will act more like a
liquid.
The recorder writes down the group’s responses
on the worksheet.
Performance
Assessment:
Students will be assessed in two ways: by group participation and completed worksheets.
Conclusions:
It’s
not always so easy to say definitely that a substance is a solid,
liquid, or
gas. Some materials, like
cornstarch, when mixed with water can act more like a solid, when
treated a
certain way and more like a liquid when treated a different way.
Shaving cream, on the other hand, seems to be unusual because it
is a
liquid soap with a lot of gas bubbles mixed in it.
It’s the gas that makes it so frothy and thick that it is able
to keep
its shape and support light objects like a penny (a solid).
When the shaving cream stands overnight, the liquid in it
evaporates, and
all that is left where the gas bubbles once were is a very light and
thin, solid
layer of soap. So you can see that
shaving cream has the characteristics of all three states.
References:
http://www.tsbkm.com/cgi-bin/lessonlocator/view_activity_info/137
http://www.exploratorium.edu/science_explorer/ooze.html
Solid,
Liquid, or Gas?
Part 1
1.
Draw a picture of how your lab setup should look.
2.
Place a small amount of shaving cream on a paper towel. Describe
the
properties of the shaving cream. Is it a solid, liquid, or a gas?
Why do you think so?
Write your responses on the worksheet.
3.
Next, squirt a small amount of shaving cream on the other paper
towel.
Gently place a penny on top of it.
What happens?
Write your response on the worksheet.
4.
Rub some shaving cream between you thumb and index finger.
How does it feel?
Write down your response.
5.
Let the shaving cream set out overnight.
Did you notice any change?
Examine the shaving cream blob with a magnifying glass.
What does it look like?
Write your responses on the worksheet.
Solid,
Liquid, or Gas?
Part
2
1.
Draw a picture of how your lab setup should look.
2.
Mix 2 tablespoons of cornstarch (30 ml) with 1 tablespoon of water (15
ml).
Describe the properties of the cornstarch and water mixture.
Stir the mixture quickly, then slowly.
Does the mixture have attributes like a solid or a liquid? Why
do you
think so? Write your response on
the worksheet.
3.
Put a small amount of the mixture in you hand.
How does it feel? Write down
your response.
4.
Now, try to pour a little of the mixture. What
happens?
5. Write two unusual things that you observed about the cornstarch and water mixture.
http://www.seed.slb.com/en/scictr/lab/cornstarch/index.htm
http://www.exploratorium.edu/science_explorer/ooze.html
Back to the SMART home page.