Featured DEMO: A Penny for Your Thoughts

Featured DEMO

6

A Penny for Your Thoughts

Purpose

To observe a chemical transformation firsthand.

Materials and Safety

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  1. List the equipment used in the demonstration.

  2. Briefly describe your observations of each substance used in the demonstration.

  3. Safety is extremely important in the chemistry lab. Write three important safety considerations for this demonstration.

Procedure and Observations

Record your observations for each step of the demonstration.

  1. Place a beaker containing zinc filings and sodium hydroxide on a hot plate set to 4.

  2. Use tongs to pick up the penny and place it in the heated beaker.

  3. While holding the beaker steady with tongs, remove the penny with the other tongs.

  4. Put the hot penny in a beaker of cold water to cool and rinse it.

  5. Use tongs to place the penny on the hot plate.

  6. When the penny has changed color, use the tongs to place it in the beaker of cold water.

Analysis

Working with the students at your table, spend a few minutes discussing what you observed during the demonstration. Then answer the questions individually on your own paper.

  1. Describe what happened to the penny during the demonstration.

  2. What do you think turned the penny silver?

  3. What do you think turned the penny gold?

  4. Making Sense Do you think you made real gold? Why or why not? How could you find out?