Flinn’s Exploring Chemistry™—Thermochemistry

Introduction

Understanding heat and energy changes has never been easier with Flinn’s Exploring Chemistry™! Students witness important thermochemistry concepts—understanding the difference between endothermic and exothermic processes and measuring heat energy—to ensure their success in building and connecting knowledge. Build a solid foundation for student achievement with five activities—one experiment, two demonstrations and two POGIL® activities.

Concepts

• Heat
• Calorimetry
• Endothermic reaction
• Heat capacity
• Combustion reactions
• Enthalpy change
• Specific heat
• Exothermic reaction
• Dependent and independent variables

Background

What’s in This Thermochemistry Package?

Your package includes enough chemicals and specialty equipment to perform the lab and learning activities listed. Quantities of chemicals are sufficient for three classes of 30 students working in pairs! Instructions for all activities may be found in Thermochemistry, Volume 10 in the Flinn ChemTopic™ Labs series, which is included in the package. Student handouts for each activity may be reproduced for classroom use. Comprehensive instructions and teacher notes, with real sample data and answers to all questions, are also provided for each activity. All of the lab activities were created under the direction of the Flinn Scientific Curriculum Advisory Board of master teachers and then tested and retested to optimize safety and success. These activities truly are the best of the best!

The following activities may be performed in any order. One possible lesson plan is described.

• Discovering Instant Cold Packs: Experiment
• Calorimetry: POGIL^® Activity
• Bond Energy: POGIL Activity
• Specific Heat: Demonstration
• Whoosh Bottle: Demonstration

Experiment Overview

Discovering Instant Cold Packs
Instant cold packs have commercial applications in first aid, among other uses, which makes students readily excited to do this lab! The lab begins by measuring ammonium chloride and dissolving in water to produce a temperature change. Students measure the temperature change that occurs and determine the heat change for this process. Note: The ChemTopic book instructions use ammonium nitrate. Due to the hazard of ammonium nitrate, ammonium chloride, which has the same great results, has been included in this kit (see Table 1). {12253_Overview_Table_1} Calorimetry POGIL^® Activity
In this activity, students explore how mass, temperature, heat energy and type of substance are related. Students work their way through leading questions and helpful models to understand what occurs when different substances are heated.

Bond Energy POGIL Activity
Students explore how energy changes can be approximated for chemical reactions. Students learn how the breaking of bonds in the reactants rearrange to form the products and the changes in energy that are involved in this process. Furthermore, an understanding that the net energy change for a reaction is called the heat of reaction or the change in enthalpy (ΔH) is clarified in this activity.

Specific Heat
A great super value demo you can do over and over again every year! Three different metals of equal mass are heated to the same temperature in a boiling water bath. The metals are then added to three insulated foam cups, each containing the same amount of water. Show students that the resulting temperature changes are different for the three metals.

Whoosh Bottle
Combustion reactions represent the most important application of thermochemistry. The Whoosh Bottle is a classic student and teacher favorite to demonstrate combustion reactions! The chemicals included are enough for four demonstrations, but the 5-gallon bottle may be used up to 20 times.

Materials