Heat Transfer Lab Rotation: Conduction, Convection, and Radiation

Ask students, "What are you going to be learning today?".  Students should respond with the essential question, "How does energy transfer through various systems in the natural world?" (I keep this posted on the board.  Students also have it in their Unit Plan).

Explain that the students will specifically be introduced to Skills 3, 4, and 5 listed in the Unit Plan:

1. I can solve problems based on my understanding of heat transfer (conduction, convection, radiation).
2. I can provide evidence that the amount of energy needed to transfer to change the temperature (average kinetic energy of the particles) of an object depends on the type of matter and the mass of the object.
3. I can support the claim that when the kinetic energy of an object changes, that energy has been transferred to or from the objects in the system (energy is conserved).

Then, ask the students to make as many connections during the lab to the following ideas/concepts:

1. Conduction, convection, and radiation
2. How the type of matter or mass of an object affects heat transfer
3. How energy can be tracked through a system (that when one object gains energy, another loses energy)

Remind them if at any point during the lab they connect to any of these ideas, they should share that connection with you or a fellow student!

This lab station rotation asks students to identify evidence of radiation, convection and conduction.  Students write well developed paragraphs and cite text that connect to the lab stations.  In a previous lesson, students "talked to the text" to identify some textual evidence of heat transfer.  They will use this resource to answer the questions here.  This article along with a copy of an article that a student "talked to the text" on is included.  (Interested about talking to the text?  Here is a quick modeling session I did with my kids with this article.)

Procedures for all of these labs are contained in the student lab document.  Display these procedures from the document at the lab stations so that students can refer to them as they work at each station.  With the whole group, go over each station and the safety precautions involved.  

Station A:  Convection Box

Safety Precautions:

Students must wear goggles while performing this task.

If any item is on fire and a student is concerned, students should place that object in the sink.

Procedure:

1. Put on safety goggles.
2. Light the candle in the box with a match.
3. Take a piece of touch paper and fold it the “hot dog” way.
4. Light the touch paper on fire with a match.  Blow it out so it is smoking and glowing red.
5. Take the smoking touch paper and place it over both of the chimneys.  Pay careful attention and make observations.  If you want to watch it again, follow the previous procedure (Steps 1-5).
6. Draw and describe your observations on your lab sheet.  

Teacher Tips:  

• You can purchase a convection box and touch paper here. 
• When students fold the touch paper "hot dog" style and put it in the tube, some students want to "shove" it all the way in the tube and let go.  They should only be putting the paper in a small distance and then remove it.
• Students have a tendency to drop their used matches in the tubes.  This will ruin the candle below if the matches get caught in the wax.  

 Station B:  Radiometer

Procedure:

1. Turn on the flashlight and point it at the object.  Observe what occurs and record your observations on the lab sheet.
2. After turning on the utility light, point it at the object and observe what occurs.  Record your observations on the lab sheet.  It is important that you write down what happened differently with each light source.

Teacher Tips:

• You can purchase a radiometer here.
• Radiometers are very fragile!  Have the students be very careful.  I tell the students that they may not pick it up off the lab table.

Station C: Conduction Rod

Safety Precautions:

Students must be careful with the boiling water.  Students must wear safety gloves to handle the hot water containers.  

Procedure:

1. Measure 200 mL of the room temperature water and put it in the Styrofoam container with the label “Room Temperature Water.”
2. Measure 200 mL of the boiling water and put it in the Styrofoam container with the label “Boiling Water.”
3. Make sure that the metal rod is connected between the two lids and the metal (silver) thermometer is in the lid labeled “Boiling Water.”  Place the lids on their appropriate containers.
4. Record the temperature of the two cups every minute for ten minutes.  Remember, we always use the metric system!  Your temperatures should be in Celsius!

You can purchase a conduction apparatus here.

Station D:  Conductometer

Safety Precautions:

Wear safety goggles!

Hot wax can burn!  Do not touch!

Procedure:

1. Take a small piece of wax in the tiny hole (groove) at the end of each metal spoke.
2. At the center of the spokes, there are letters.  Based on these letters, label what you think each spoke is made of.
3. Put the center of the device over the Bunsen burner.
4. Record the order that the wax melts by putting a number on the line by each spoke on your lab sheet, number 1 being the first to start melting.

Teacher Tips:

• You can purchase a conductometer here.
• Each rod on the conductometer is made of a different type of metal that will melt the wax at different rates.

This "exit slip" of sorts I use as a closure for the first day of the lab rotation.  Then, I use it on the second day to promt a discussion about misconceptions and to form conference groups.  After class, I sort the students completed diagrams into groups of learners with similar needs.  

Prior to completing this formative assessment, students have been working towards mastery on drawing diagrams as scientific representations.  For some insight into this previous instruction, check out Potentially Amazing Lab Rotations.  It includes a video of a mini lesson on drawing diagrams.

Below is an example of a student's work:

A few things I look for in diagrams:

1.  A title: This student actually forgot a title when she turned it in and added the title "Heat Transfer in Oceans" when she received feedback from me.

2.  Labels:  Students should label radiation, convection, and conduction accurately on the picture.

3.  Caption:  In the caption, the student should explain where radiation, conduction and convection are occurring.  Their caption should indicate an understanding of why they know each type of heat transfer is occurring.

4.  Purpose: All of the criteria listed above (title, labels, and caption) should serve the purpose of the diagram.  Students can get "off track" and focus on one type of heat transfer instead of relating to all of them or refer to irrelevant information.  The key to purpose is taking the time to break down the question to identify what is required of them.

When I assess these, I separate them into piles of similar learners and pull small groups the following day to discuss common misconceptions.  For example, I may meet with a group that needed to work on developing explanations in their captions, a group that needs help finding the purpose, and a group that is forgetting the importance of titles/labels.

This can also help me identify common misconceptions among my students that I need to address before the second day of this lab rotation.

Below are some videos that go through some student work and an explanation of the acronym "ABCDE" that I use to help students format their scientific explanations.  The videos will help you gain an understanding of this format, student exemplars, and feedback to provide the students.  While the videos do not describe all of the stations, it will give you enough insight to see the patterns in the student work samples I included in the resources so you can identify them with your own students.  The student work samples in the resource section do include student work for all of the lab stations.

Station A:  ABCDE

Station C:  Data!  Use it!