In this lab, students will explore the process of condensation. Students will investigate how water vapor condenses, and then they will conduct a comparison test to see if cooling water vapor has an effect on the rate of condensation.
Elementary or middle school
By the end of this lab, students should be able to
- Describe that the process of changing matter from a gas to a liquid is called condensation.
- Explain that the surrounding temperature can affect the rate of condensation for a gas.
This lab supports students’ understanding of
- States of Matter
- Phase Changes
- Physical Changes
Teacher Preparation: 20 mins
Lesson: 50 minutes
- 2 pitchers
- Hot water- from the tap or use a warming pot/hot plate to warm up water
- Ice cubes (one per group)
- 1-cup measuring cup
- 2 Tall clear plastic cups (per group)
- 2 Wide clear plastic cups (per group)
- Paper towels
- Sauce pan/pot with lid
- Timer (one per group)
- Always wear safety goggles when handling chemicals in the lab.
- Students should wash their hands thoroughly before leaving the lab.
- When students complete the lab, instruct them how to clean up their materials and dispose of any chemicals.
- Exercise caution when using a heat source. Hot plates and/or heating devices should be turned off and unplugged as soon as they are no longer needed.
- Be cautious when moving around the heat source. Do not reach over it, tie back hair, and secure lose clothing.
- Warm students about handling the hot tap water, exercise caution and ensure heat protective gloves are available for use.
- This activity calls for both small and wide clear plastic cups. Be sure the cups fit together, as shown in the picture. The wide cup should be used to hold the hot warm, and is placed on the bottom. The small cup is turned upside down and placed in the wide mouth cup. They should make a seal together. Be sure that the smaller cup, that will be inverted is completely clear.
- You will need a way to warm water for the initial demonstration. I suggest using a sauce pan and single burner. Place the water on the burner and wait about 10 minutes before starting the demonstration (this will be used for students to answer the prelab questions). Leave the lid off to get started. If a single burner/saucepan is not available, consider using a microwave to heat the water or recording the process at home and showing the students a video recording in order to complete the prelab demo.
- You will need hot water for the experiment, but please note that it does not and should not boiling or extremely hot for the experiment portion. Using hot tap water is recommended.
- Depending on what is available in your classroom, students can obtain hot water for the experiment from the tap, or they can use a hotplate or microwave to heat the water. Make sure you have proper heat protective gloves/oven mittens available for students to use.
- Before you have students start working on the activity, have a discussion about where they believe they have experienced condensation and what their definition is. Use examples such as a glass of lemonade during the summer, fogged up windows in the winter, etc.
- I have students work in groups of 2-3 for the lab.
- During the experiment when students put the ice cube on top of the cup they should see that the rate of condensation increases due to the temperature decrease outside of the cup.
For the Student
When changing matter from one state to another, heat energy can be added or removed. The phase change that occurs when matter changes from a gas to a liquid is called condensation.
You will be investigating what happens when heat energy is removed at different temperatures.
To simulate how gas changes to a liquid and how to change the rate of condensation.
- In front of the room there is a pot of water boiling, what do you think will happen when the pot is covered with a lid?
- Go to the front of the room and ask for the lid to be placed on top of the pot. Watch what happens. Describe what you see:
- Hot tap water
- 1-cup measuring cup or graduated cylinder
- Ice cube
- 2 small clear plastic cups
- 2 Wide clear plastic cups
- Magnifying glass
- Paper towels
- Fill the 1-cup measuring cup (or graduated cylinder ~235ml) with hot water and pour it into the wide mouth cup.
- Repeat step 1 and put a cup of hot water in the second wide mouth cup.
- Quickly place each of the empty tall clear plastic cups upside down on top of the water filled cups to create a closed container. See photo 2 for reference.
- Place a piece of ice on top of one of the inverted cups. See photo 3 for reference.
- Start the timer and observe the cups for 2 minutes.
- Use the magnifying glass to look at the sides and top of both inverted cups during the 2 minutes.
- Remove of the piece of ice and put it in the sink then take cups apart. Examine the tops of each cup. Record your observations for each cup in the data table below.
- Clean-up as directed by your teacher.
|Hot Water condensing||Hot water condensing (Ice Cube present)|
- Compare the amount of water on the inside of the top of each cup. Which top cup has more water in it?
- Based on your observations, does cooling water vapor increase the rate of condensation? Explain.