Demonstrate the importance of conserving heat energy with this classroom experiment.
Skills supporting learning standards: developing a hypothesis, conducting experiments, recording and analyzing experiment results
- 3 glass jars
- 3 thermometers
- Bubble wrap
- Hot plate or microwave
- Oven mitt
- Copies of the “Heat Savers” student activity sheet
This classroom experiment will explore the role of insulators in conserving heat energy.
- To begin, share background information with students:
- Heating uses the most energy in the home. More than 40 percent of the energy we use in our homes is for heating.* As a result, conserving heat energy is an important way to reduce energy consumption.
- Materials that resist the flow of heat are called insulators. This experiment will test whether newspaper or bubble wrap makes a better insulator.
- Set up the experiment materials and distribute copies of the student activity sheet to the class. Explain the steps of the experiment described on the activity sheet. Since the experiment features a hot plate and hot water, teachers should present the experiment as a demonstration. Students may assist you as is appropriate for them. For example, students might help wrap the glass jars and read the temperature on the thermometers.
- Describe the procedure to students:
- Use tape to completely cover one jar in newspaper and another in bubble wrap. Cut squares of newspaper and bubble wrap to use as lids on top of the jars. Leave a third jar uncovered.
- Heat the water on a hot plate or in a microwave and carefully measure one cup of hot water into each jar. (NOTE: Only teachers should heat and pour the hot water, using a mitt.)
- Immediately take the temperature of the water in each of the three jars. Have a student read the temperature to the class so students can record the results on the student activity sheet.
- Cover the newspaper and bubble wrap jars with the corresponding “lids.” Leave the uncovered jar open.
- After 10 minutes, remove the lids and record the temperature of the water in each jar again.
- Repeat the procedure after another 10 minutes.
- Allow students to complete their activity sheets. Then discuss their findings as a class. What is their conclusion? (The bubble wrap generally works as a better insulator than newspaper or an uncovered jar. Air is a good insulator, and each bubble in the wrap contains trapped air.)
- Explain that insulators can also be used to conserve heat at home and in school. Plastic window films and heavy curtains trap air near drafty windows, keeping the air warmer inside the building. Insulating materials between walls also helps to keep buildings warm.