Lesson 10 of 15
Objective: SWBAT Identify the phase change of melting through a hands on demonstration.
Teacher Tip: This lesson is about the changing states of matter, specifically melting. Students will explore what they know already about melting and then will create a device to prevent ice from melting using basic materials. You will need the following for each small group: one thermometer, one cube of ice, piece of foil (approximately 5 in x 5 in), paper towel, Styrofoam cup. This lesson explores NGSS MS-PS1-4 as students are explaining the effects of removing and adding heat to the solid state of matter.
To start this lesson, students will individually reflect on the following prompt in their student notes sheet:
Do you think a solid can change into a liquid? Explain.
After 3-4 minutes, I will ask a few students to share their responses with the class.
Students will have an ice cube on their table sitting atop a paper towel. They are asked to answer the following prompt together:
Using the ice cube on your table, explain what you can do to melt it as quickly as possible.
Try it. What happened?
First, students will devise a plan for melting the cube as a small group. Then, once you see they have the procedure or plan for melting is written, they can try it and record their results. Once all groups have attempted to melt the ice, I ask them to share what they've done to melt the ice.
For this next section, students will individually reflect on melting up to this point. They will respond to the following prompt in their notes sheet:
How can you change a solid to a liquid?
Can you change another solid to liquid, besides ice? Explain.
This should be fairly simply for them to answer considering they've just melted a solid into a liquid. However, if they are stuck, ask them what they did to change the ice to water.
Students are now faced with the challenge of creating a thermal insulator (something to prevent the melting of the ice cube). On the student notes sheet, students can read along as you explain the procedure and the materials available. Make sure to wrap the ice cube in the paper towel (I use a brown towel from the school as you can see melted ice much easier). This is how they will measure the amount of melting that has occurred.
Students will explore the materials, write a procedure for building, build it and then test it. They will keep data for 5 minutes, recording initial temperature in the device and final temperature. They will complete 2 trials.
For a final task, student will individually reflect on the lesson by answering the following prompt in their notes sheet:
Explain how a solid can change to a liquid. Use words from the word bank below.
molecules heat energy liquid solid motion
A solid can change into a liquid when…
I know this because, when we…