Thermochemistry - Sample Lesson Plan

Today I’m sharing a sample 5E multi-day lesson plan that can be used to teach on heat and calorimetry within the context of thermochemistry.

I’ll briefly provide a description of each of the phases below then provide a link where you can access the full lesson plan.

Here are the objectives for the lesson:

• Given the terms “temperature” and “heat,” SWBAT correctly compare and contrast the meanings.

• Given a set of calorimetry conditions, SWBAT correctly calculate the amount of energy given off or released as heat during the process.

• Given the specific heat of various substances, SWBAT correctly predict relative amounts of energy needed to produce the same change in temperature.

Engage:

After sharing the lesson objectives with my students, I then proceed to show them a picture of a young lady with her tongue frozen onto the North Pole (Yes! The literal North Pole!) I ask them to draw a picture that shows how her tongue froze onto the pole.

As a teacher, this allows me to gauge for common misconceptions about the direction in which energy is transferred as heat.

Explore:

I then proceed to have students explore the difference between heat and temperature by walking around with a plastic tray and a metal tray (preferably silver) and asking students to touch them and tell me which tray is “colder.” The response normally given during this part is that the metal tray is “colder.” Based on their decision about which one is “colder,” I then give each pair of students two spoons (again, one plastic and one metal) and ask them to predict which one would prevent an ice cube from melting the fastest. They normally predict that the metal spoon will because the metal tray felt the “coldest.”

So, I give them ice cubes and let them try it. They hold both spoons in their hands, and contrary to their initial prediction, the ice cube in the metal spoon melts noticeably faster. I ask them to talk with their partner to try to explain why what happened didn’t line up with their original prediction. Then, I reveal the fish tank thermometers that are taped to the back of the two trays that I originally showed them. The fish tank thermometers reveal that both trays are at the same temperature. So, I give the students time to try to generate an explanation again after they know this new piece of data.

This exploration eventually leads us around to addressing a common misconception that heat and temperature are the same. However, temperature is a measure of the average kinetic energy of particles, while heat is the flow of energy from objects at a higher temperature to objects at a lower temperature.

Explain:

We then proceed to take notes on the different between heat and temperature, the concept of specific heat (which can also be connected to the exploration activity), calorimetry, and calculations involving heat transfer.

Extend:

Then, the students divide into four groups and do a jigsaw activity in which they work practice problems related to heat transfer/calorimetry. Each group is responsible for working one of the questions. Then, students are divided into new groups of four students each, where each one of the students had worked a different practice problem in the original groups. They then take turns teaching each other the practice problems that they had worked. This strategy helps students develop a higher level of understanding, since teaching a concept requires one to first know it for him/herself.

Secondly, students are given materials in which they can design a calorimetry experiment to determine how many calories are in a serving of snack foods. This lab plan from the American Association of Chemistry Teachers (AACT) provides more details on how this activity works.

Evaluate:

The lab packet is used to assess student achievement of the learning objectives. The way in which the lab assesses the objectives is detailed below.

• Objective 1

#8. How are heat and temperature related, yet different?

• Objective 2

In the calculations section of the lab, the students use the calorimetry data they collected from the lab to calculate the heat released by the snack food that was absorbed by the water.

• Objective 3

#6. Ammonia has a specific heat of 4.70 J/g oC. If ammonia had been used in the soda can calorimeter instead of water, would we have observed a greater or smaller increase in temperature? Why?

#7. Ethylene glycol (antifreeze) has a specific heat of 2.42 J/g oC. If ethylene glycol had been used in the soda can calorimeter instead of water, would we have observed a greater or smaller increase in temperature? Why?

I hope you find this lesson plan a helpful starting place for generating some ideas for your thermochemistry unit! Click here to view a copy with some of the accompanying materials!

Resources used in designin the lesson:

Engage and Explore activities – Save the Penguins STEM Teaching Kit, Dr. Christine Schnittka

Extend – “How Much Energy Is in Your Snack Food?” – AACT, Diana Simpson