Flinn’s Exploring Chemistry™—Solids, Liquids and Solutions Package

Introduction

Teaching the properties of solids, liquids and solutions will be a breeze using Flinn’s Exploring Chemistry™! Phase changes, intermolecular forces, solubility and saturated solutions are a few of the concepts students will have a hands-on approach to master. Complete with two demonstrations, two experiments and two POGIL™ activities—this package guarantees success to solidify your lessons!

Concepts

• Surface tension
• Phase changes
• Melting point
• Kinetic–molecular theory
• Solution
• Solute
• Solubility
• Solvent
• Gas solubility

Background

What’s in this Solids, Liquids and Solutions 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 Solids and Liquids, Volume 11, and Solubility and Solutions, Volume 12 in the Flinn ChemTopic™ Labs series, which are 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.

• It’s Just a Phase (Experiment)
• Factors Affecting Solution Formation (Experiment)
• Molarity (POGIL™ Activity)
• Solubility (POGIL Activity)
• Surface Tension Jar (Demonstration)
• Alka-Seltzer^® and Gas Solubility (Demonstration)

Experiment Overview

It’s Just a Phase
Collecting and plotting data is one of the best ways to have your students observe important trends. Furthermore, when it’s their own data, students get excited about learning! Students take a look at the temperature changes and the energy changes that take place when a liquid freezes or a solid melts.

Factors Affecting Solution Formation
Students have the chance to experiment on an important chemical in agriculture—copper sulfate. This is an inquiry based lab and question asking and answering is key in the investigation of the effects of crystal size, degree of mixing and temperature on the rate at which copper sulfate dissolves in water.

Molarity
Mixtures are apart of everyday life such as juices or medications. This activity focuses on molarity—a ratio of number of solute particles to the volume of solution. Students learn about molarity and how to represent concentration quantitatively.

Solubility
In this activity students look at different solutes, such as salt, sugar or minerals, dissolved in water and other solvents in varying amounts and learn to quantify the amount of solute that is dissolved in a solution. Ensure that students grasp these important concepts by answering clarifying questions.

Surface Tension Jar
Prove to your students how what may seem the simplest concepts, can also be the most amazing! Surface tension is a force, in fact, it’s powerful enough to prevent water from spilling out of an open jar when it is turned upside down! This demonstration is a super value—the materials may be used over and over again to amaze your students every year with the concept of surface tension.

Alka-Seltzer^® and Gas Solubility
Students may draw knowledge from everyday experience—the solubility of many solid and liquid solutes increases as the temperature increases. However, this demonstration shows the students that in the case of gases this generalization is always wrong! An Alka-Seltzer tablet can teach students the effect of temperature on the solubility of a gas.

Materials