States of Matter
Barbara Pawela Retired
Objectives:
Grades 3-6
The students will be able to:
A. Define matter.
B. Identify the states of matter.
C. Tell about the properties of each state of matter.
D. Demonstrate an understanding of the difference between a physical and
a chemical change.
Materials needed:
a variety of solids Ziploc plastic bags hot plate
a variety of liquids clear plastic glasses crucible
spray perfume 2 Erlenmeyer flasks ice
2 Tbs. powdered sulfur round balloons clear container
2 Tbs. iron filings food coloring 4 cans
baking soda acetate fabric 2 beakers or jars
vinegar 50ml acetone
1 tsp. salt watch glass
Strategies:
Activity I:
1. Display different solids and liquids.
2. Put a variety of small solid objects into Ziploc bags, and have a member
of each group pick-up the bags for each student in the group
3. Discuss the definition of "matter".
4. Ask the students to take out, look at, and touch the objects. Ask if
they can see the objects? Introduce the word "visible".
5. Together discuss the other properties.. Tell the students to try to
put their pens through the desk. Ask if they could do so easily? Tell
them to do the same thing with some of the other objects. Together
discuss that one cannot go through solids easily. External force has
to be applied.
6. Ask the students if the objects keep their shape easily? Discuss and
conclude that they do if no force is applied to them.
Activity II:
1. Take ice cubes between your hands. Hold your hands up and ask what is
happening.
2. Together discuss the change of phase from a solid to a liquid.
3. Pass out clear plastic glasses half-filled with water. Point out the
other liquids on the table. Ask what other liquids they know?
4. Tell the students to try to put their pens in the water. Discuss and
conclude that objects can go through a liquid easily.
5. Have the students pour the water out of the glass into the Ziploc bag.
Discuss what happened and come to the conclusion that a liquid has a
definite volume, but not a definite shape. Instead it takes the shape
of its container.
6. Put about a liter of water in a clear container. Squirt 4 to 6 drops
blue or green food coloring into the water. Observe what happens.
Discuss "fluidity".
Activity III:
1. Ask the students what is in front of their nose? Tell them to take
an index card or piece of paper and fan themselves. Discuss and
conclude that the breeze is made by moving air. Have the students
blow up their balloons and then let the balloons deflate. Ask if they
could see the air or the substance that was blown into the balloon.
Introduce the terms "gas" and "invisible".
2. Spray some perfume. Let it disperse throughout the room.
3. While the perfume is dispersing, take the Erlenmeyer flask, in which
the water should be boiling for at least a minute, off the heating unit
and immediately place the balloon opening over the flask's mouth.
4. Let the water balloon cool (the balloon will be sucked inside out into
the flask). If the flask is carefully heated again the balloon will
expand and come out of the flask. Discuss what was happening.
5. Discuss the aroma in the room. Ask how the aroma was dispersed.
Activity IV:
1. Give each group a can containing ice. Let water condense on the outside
of the cans and then ask if the cans are leaking. Discuss from where
did the water come. Together continue discussing the change of phase
from a gas to a liquid.
2. State that matter can undergo other types of changes besides the change
of phase. Have the students tear their paper. Have them mold the clay
into different shapes. Discuss the fact that, though a change has
occurred, the basic material is the same substance.
3. Cut an apple into pieces. Again point out that cutting an apple was a
physical change and the substance of the apple was the same. Place some
of the apple pieces into the crucible. Add a little water and place
the crucible on the hot plate to cook. Leave some of the raw apple
pieces exposed to the air.
4. Put 1/2 tsp. salt into 50ml water. Stir until the salt dissolves.
Take about 10 ml of solution and put on a watch glass. Place on a
hot plate.
5. Take 1 tsp. powdered sulfur and mix it with about 1/2 tsp. iron
filings. Mix the sulfur and iron. Place a magnet over the mixture.
The iron filings will be pulled out by a magnet. Discuss and conclude
that the mixing had been a physical change.
6. Check on the apples and on the evaporating salt solution. The apple
should have cooked some. Discuss how the apple has changed. Conclude
that the apple is different from the raw apple and will not change
back. Look at the watch glass after the water has evaporated. Look at
the residue and discuss what happened.
7. Burn part of the paper. Discuss and conclude that the paper has
undergone a chemical change. The actual substance has changed to
something else, and burned paper cannot be returned to the original
substance.
8. Heat the 1 tsp. powdered sulfur mixed with 1/2 tsp. iron filings. Observe
what happens. A gas is given off. A new substance has formed. Allow it
to cool. Test for magnetic attraction. Discuss and conclude that a
chemical change occurred.
9. Cut a small piece of acetate fabric. Ask what kind of change this was.
Put the piece of fabric into 50 ml acetone in a beaker or similar jar.
The fabric will dissolve. Together discuss that this is a chemical
change. Repeat the process dissolving styrofoam in the acetone.
10. Give each group a candle. Light the candles. Observe and discuss what
is happening. Conclude that the burning candle is an example of both a
physical and chemical change. Some of the wax melts into a liquid and
later cools down and solidifies back into its original substance. Some
of the melted wax was heated enough to change into a gas which burned.
Performance Assessment:
Part of the assessment are the students' responses during the discussions.
The final part of the assessment is as follows:
You have been hired by a sea-bordering, desert country to provide
drinking water from sea water. You are to purchase materials and design
a process to provide fresh water. Explain what equipment and materials
you would use. Draw a diagram and explain your procedure.
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