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Properties of Matter

Investigation 3 – Lab

Back to Investigation 3

BE PREPARED

Supplies and Equipment:

Class Materials:

1 400 ml beaker
200 ml vegetable oil
ice cube

Group Materials:

1 white plastic bucket 1 gram cube
1 paper clip
1 large (12 g) gram bear 1 acrylic cylinder
1 10 gram weight
1 ping pong ball
1 moon ball
1 woodblock
1 metal cube
1 kidney bean
1 plastic marble
paper towels

Individual Materials:

1 Student Data Record

Teacher Preparation:

1. Fill a plastic bucket 2/3 full of water for each group.

2. Fill the 400 ml beaker with 200 ml of vegetable oil.

3. Divide the class into five cooperative groups.

Instruction:

Direct each student group to obtain the following necessary materials from the distribution point: one (1) plastic bucket, one (1) gram cube, one (1) paper clip, one (1) large (12 g) bear, one (1) acrylic cylinder, one (1) 10 g weight, one (1) ping pong ball, one (1) moon ball, one (1) wood block, one (1) metal cube, one (1) kidney bean, one (1) plastic marble.

GET FOCUSED

Investigation Three introduces students to the concept of density of water, compared to other substances and objects.

INVESTIGATE

Trial 1

1. Students will make their first prediction of the Investigation in this Trial. Will ice float in oil?

a. Show students the ice cube and the vegetable oil.

- - Based on their observations, ask students to use the Prediction Cognitive Tool. Predict whether the ice cube will float or sink in the vegetable oil.
  - Direct students to record their prediction in Problem 5a of their Student Data Record.

b. Place the ice in the 400 ml beaker with the oil.

Ask students: Did it float or sink? Students should record their answers in Problem 5b of their Student Data Record. Students should observe that the ice floats.

c. Explain: to students that they will continue the experiments and will revisit the ice cube later.

Trial 2

2. To begin the Investigation, students will make and test their predictions about sinking and floating. The question they will be answering is:

Will it float?

a. Ask students: What do you think determines whether an object sinks or floats? Student answers may vary.

Direct students to locate Problem 6 in their Student Data Record. Based on their observations, ask students to use the Prediction Tool again.

Tell Students: The first object we are going to test is the gram cube. Predict if it will sink or float.

Direct students: to examine the object and then choose their prediction. Students should record their predictions in the second column of the Table in Problem 6.

b. Tell students: Drop the gram cube in the water to test it. Did it sink or float? Direct students to record their findings in the Table their Student Data Record.

c. Instruct students: to predict and test the remaining objects in the chart in the same way.

Trial 3

3. In this Trial, students will investigate the density of solid objects in relation to the density of water. The question they will investigate is:

How does the density of a solid effect floating and sinking?

Direct students to look at Problem 7 in their Student Data Record. Based on the information provided, ask students to use the Prediction Tool.

Tell students: Look at the ping pong ball. Its density is less than the density of water. Predict whether it will float or sink, and record your prediction in the chart.

a. Instruct students to place the ping pong ball in the water and record what happens in the Table in their Student Data Record.

b. Repeat Steps b and c until all of the objects have been tested.

Trial 4

Students will re-examine the ice cube in oil to see how it has changed over the course of the lab.

Can different states of matter have different densities?

a. Instruct students to observe the 400 ml beaker containing the ice cube.

b. Ask students: What has happened to the ice cube? Students should indicate that the ice cube has melted and changed to liquid water.

c. Ask students: Is the water floating or did it sink to the bottom of the cooking oil? Students should indicate that the water has sunk to the bottom of the oil.

Direct students: to record their answers in Problem 8 of their Student Data Record.

d. Tell students they will be analyzing what happened in the PostLab.