This article provides a description of concrete models that represent different classifications of matter and directions for their use in the classroom. By using colored paper clips, students can represent pure substances, mixtures, elements, and compounds and then discuss their similarities and differences. This model is advantageous for the beginning student who would not know enough about the detailed composition of simple materials like milk, brass, sand, and air to classify them properly. Examples of isomers and allotropes are also created to introduce those concepts at an early stage and in an easy-to-understand format. This classroom activity would be especially suitable for a collaborative- or cooperative-learning environment, but could be adapted for individual learners.
Supplement
Answers to the student questions presented in Box 1 are available.
The "Chemistry Teacher Connection" (CTC) is especially for high school chemistry teachers. For only $40/year, it offers an online-only subscription to CLIC along with membership in the Division of Chemical Education, normally $65/year. CTC subscribers receive access to all articles and supplements from 1996 through the current issue.
Through special arrangement with the ACS, JCE High School CLIC is now able to provide subscribers with online access to Chemical & Engineering News articles that have been selected specifically for secondary science instructors and their students.
Occasionally, collections of JCE back issues become available for donation to individual teachers, schools, or libraries. JCE matches collections with interested recipients. Recipients pay shipping costs or pick up the collection.
For journals in other fields of chemistry visit ACS Publications.
Contents
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