Summary

In this activity, students will define entropy and be able to recognize entropy changes in chemical reactions.

Grade Level

High school

AP Chemistry Curriculum Framework

This activity supports the following unit, topic, and learning objective:

• Unit 9: Applications of Thermodynamics
  • Topic 9.1: Introduction to Entropy
    • ENE-4.A: Identify the sign and relative magnitude of the entropy change associated with chemical or physical processes.

Objectives

By the end of this lesson, students should be able to

• Define entropy.
• Recognize entropy changes in chemical reactions.

Chemistry Topics

This lesson supports students’ understanding of

• Entropy

Time

Teacher Preparation: 30 minutes
Lesson: 30 minutes

Materials

• PowerPoint slides

Safety

• No specific safety precautions need to be observed during this activity.

Teacher Notes

• My students find this to be an extremely easy way to understand entropy. They go from knowing nothing about entropy to being proficient in less than half an hour. They start by identifying teacher desks (engagement), then they rank the desks from neatest to messiest. Lastly, they complete the PowerPoint lesson, referring back to the teacher desks. Sometimes they even present an entropy award to the winning teacher!
• Teachers should prepare a photo stream of teacher desks or other examples of entropy that your students will relate to, that way it’s more meaningful to your class.