Lesson Title: Physical Properties of Ice

Taken from: http://www.sd5.k12.mt.us/glaciereft/glac3-8.htm

Grade Level: Upper Elementary

Duration: 1 class period

TEKS: 4.2(a,b,c,d), 4.7(a,b), 4.10(a), 5.2(a,b,c,d), 5.5(a,b), 5.6(b), 5.7(a), 5.11(a)

Lesson Overview:

In this lesson students will become familiar with the different properties of ice by doing hands on experiments. This would be an introductory lesson about glaciers.

Objectives:

· Familiarize students with the properties of ice.

· Teach students the idea of making predictions and experimentally testing the predictions.

· Demonstrate that ice melts faster under pressure.

· Recognize that ice can be broken up or melted by pressure and then refreeze.

Materials:

· Mason's hammer

· piece of cloth

· heavy metal key

· piece of brick or some other heavy object

· ice cubes (one per student)

· 6 additional ice cubes (kept in the freezer until class)

· goggles

Advanced Preparation:

· Put one ice cube with the metal key in the freezer the night before

Background Information:

Ice has many surprising properties. Since glaciers are made up of ice, understanding the properties of ice can help to better understand glaciers and how they are able to flow.

First, ice has both brittle and plastic properties. When subjected to sudden stress ice fractures and when the stress is even and constant, it can bend. In this activity, we will illustrate the brittleness of ice. Plastic properties are harder to demonstrate on a small scale.

Second, ice melts faster under pressure. It will even melt under pressure at subzero temperatures. This helps explain how glaciers flow. In a glacier, the pressure exerted by the mass of ice above melts the ice at the bottom of the glacier, providing a lubricating film of water, which allows the glacier to slide downhill under the force of gravity.

Third, ice has the ability to be broken up or melted by pressure and can then refreeze. This helps explain the internal flow of a glacier and how glaciers are able to flow around an object.

Procedure

1. Ask students to tell you everything they know about ice. Write their responses on the board. (If you are familiar with “KWL” this is the “K” part.) Tell students that today they are going to investigate some properties of ice.

2. Start a discussion on what the term “properties” means. Go over with students that the property of an object is like the characteristic of the object, what qualities or characteristics does the object have that makes it that object.

3. Give each student a plate or pan and place a single ice cube on each one. Ask students to carefully observe (look, touch, smell) the ice and record what they think are the properties of ice in their journal. Ask students to tell you the properties of the ice cube. Write their responses on the board.

4. Put the transparency on the overhead. Have the students make one-sentence predictions in their journals as to what might happen to the ice cube if they did the following:

· put it in the oven

· wrap it in a towel

· wrap it in a towel and place back in the freezer

· put it in a glass of water by itself

· put it in a glass of water with other ice cubes

· press down on it with your hand or foot

· leave it outside on a sunny day

· leave it outside on a cloudy day

· leave it outside on a cold day

· Review student responses after they complete their predictions.

5. Take two ice cubes and put them in a piece of cloth. Ask the students what they predict will happen if you take a hammer and hit the cubes several times. Get responses. Use the hammer and hit the ice cubes several times. Open the cloth and ask the students what has happened to the ice cubes. Place the fragments of ice into a cup and wait two or three minutes. Notice what has happened to the ice. Have students record their observations.

6. Ask the students the following questions. Discuss their answers.

· What happened when you hit the ice with a hammer?

· What happened when the pieces of ice to touch one another in the cup?

· What two properties of ice do hitting ice and allowing pieces of ice to touch one another demonstrate?

7. Now take two new ice cubes and put them in a shallow pan. Put a piece of brick or another heavy object on one ice cube. Ask students to make predictions of what will happen. Wait two or three minutes. Notice which ice cube melts faster. Also notice where the melting seems to be taking place. Have students record their observations.

8. Ask them the following questions:

· Does ice with a weight on it seem to melt faster or slower than ice without a weight on it?

· Where does the most melting seem to take place when ice has a weight on it?

· How is ice with a weight on it like ice at the bottom of a glacier? Do you think the movement of a glacier begins at the top of the glacier or the bottom? Why?

9. Take out the key that was in the freezer. Tell students you put the key on top of the ice and then placed in the freezer overnight. Have the students examine the ice and notice the location of the key. Record your observations.

· Where in the ice did you find the key?

· How do you think ice flows around an object?

10. Make a comparison chart of what happened to the ice in each situation. Review with the students the processes that caused the ice to behave in that way.

11. Have the students create a flipbook of what happened to the ice after each experiment.

Evaluation

· Evaluations will be based on the student's in-class participation, their journal responses, observations and the flipbook.

· What happens to ice when you…

1. put it in the oven?

2. wrap it in a towel?

3. wrap it in a towel and place back in the freezer?

4. put it in a glass of water by itself?

5. put it in a glass of water with other ice cubes?

6. press down on it with your hand or foot?

7. leave it outside on a sunny day?

8. leave it outside on a cloudy day?

9. leave it outside on a cold day?