Teacher Tip: For this lesson, you will need a projector of sorts and an internet connection. I use a SMART board for my projection, but you could use a regular projector and laptop, situation. The demonstrations do not require sound, so you will not need speakers. This lesson is intended for students to gain an understanding of condensation through the watching of videos and observing demonstrations that involve/cause condensation. It addresses NGSS MS-PS1-4 as students are making connections between adding/taking away heat its effects on matter.
To begin the lesson, students will individually consider the following:
Think about it- have you ever been drinking a soda from McDonald’s and all of the sudden there’s liquid on the outside of the cup? How did this happen? Explain.
They should write answers in complete sentences on their student notes sheet. If you prefer not to make copies or prefer they keep notes in a notebook, the document can be displayed to show the prompt on the SMART board. After 3-4 minutes, I will ask students to share their responses with the rest of the class.
For this section of the lesson, you will need an internet connection for the demo to be found on American Chemical Society's middle school science page (see link below). I prepare the students for the demo by explaining the procedure for completing the notes sheet.
First, I explain the set up: There are two cups of cold water. One will be placed into a Ziploc bag and sealed to block out any air. The other will remain exposed to the outside air. Students will then, make a prediction about what will happen to cup inside the bag and will do this on their notes sheet.
Next, students will make an observation about what they see happening. Then, they will record this observation in the notes sheet.
Finally, students will infer why they think there is water on the cup not inside the bag but not on the other (the one inside the bag). They will write this inference on the notes sheet.
After the demo has been shown and students have had enough time to answer and reflect (about 7-8 minutes), I will ask 2-3 students to share out their answers.
The notes sheet for this section is as follows:
Observe the demo and answer the questions below.
Predict- What do you think will happen to the cup in the bag?
Observe- Which cup had more moisture (water) on the outside of it?
Infer- Why do you think this happened?
After observing condensation in an example format, students now observe a simulation of the particles of a gas being affected by the removal of thermal energy. This requires an internet connection. I preview the response questions on the notes sheet, then show the demo.
After watching the simulation, explain what happens to the particles during condensation.
When the gas particles are…
they start to…
and change to a...
Students should respond as follows:
When the gas particles are…cooled down
they start to… move slower and closer together
and change to a... liquid
Students will now take what they've learned about condensation from the video and demo and will apply it to a drawing/model of condensation. In a kind of comic strip format, students will demonstrate the following:
Draw a diagram the shows condensation happening. Include- gas particles, cold, liquid particles, and the change that happens between them.
For the final task, students are asked to independently explain what condensation is in their own words. They can do this verbally if you are short on time or have them write their response in complete sentences on the notes sheet.