Crystals are special kinds of solids that are made up of molecules arranged in a regular repeating pattern. In some solids, the arrangements of the molecules are random throughout the material. In crystals, however, the molecules are repeated in exactly the same pattern over and over again throughout the entire material.

Group 1

Required Materials

• 2 containers (baby food jars, clear film canisters, or pill bottles)
• A cup containing warm water and a cup containing cool water
• Measuring spoon
• 2 tablespoons of copper sulfate
• 2 slides
• Dropper or straw
• Field microscope

Problem: You are going to investigate how the temperature of the water affects crystal growth. Do crystals form better when using hot or cold water?

Activity Directions

Day 1

1. Label one of your containers with an H and the other one with a C. Make sure that your name is on both containers.

2. Put 2 tablespoons of warm water in the container marked H.

3. Put 2 tablespoons of cool water in the container marked C.

4. Add 1 tablespoon of copper sulfate to each container.

5. Shake or stir until all of the copper sulfate is dissolved.

6. Label two microscope slides, one with an H and the other one with a C. Using a dropper or straw put two drops of liquid from container H on to slide H.

7. Put two drops of liquid from container C on to slide C.

8. Put these two slides where they will not be disturbed so that you can observe them tomorrow.

Day 2

1. Use your Ultrascope to observe both slides.

2. Record your observations in your science notebook by writing and drawing what you see.

3. Write 5 sentences about the differences between the crystals grown using warm water and the crystals grown using cool water.

4. Did you find the answer to your problem? Be prepared to share your results with the rest of the class.

Group 2

Required Materials

• 2 containers (baby food jars, clear film canisters, or pill bottles)
• Container of warm water
• Measuring spoon
• 2 tablespoons of copper sulfate
• Dropper or straw
• 2 microscope slides
• Field microscope

Problem: You are going to study the effects of shaking or stirring on solutions used to make crystals. Does shaking or stirring solutions produce better crystals than solutions that have not been stirred or shaken?

Activity Directions

Day 1

1. Label one of your containers with an S and the other one with an NS. Make sure that your name is on both containers.

2. Put 2 tablespoons of warm water in the container marked S.

3. Put 2 tablespoons of warm water in the container marked NS.

4. Add 1 tablespoon of copper sulfate to each container.

5. Shake or stir container S until all of the copper sulfate is dissolved. Do not shake or stir the copper sulfate in the container marked NS. Allow this to sit for about 5 minutes.

6. Label two microscope slides, one S and one NS. Using a dropper or straw put two drops of liquid from container S on to slide S.

7. Put two drops of liquid from container NS on to slide NS.

8. Put these two slides where they will not be disturbed so that you can observe them tomorrow.

Day 2

1. Use your Ultrascope to observe both slides.

2. Record observations in your science notebook by writing and drawing what you see.

3. Write 5 sentences about the differences between the crystals grown using the solution that was stirred or shaken and the crystals grown using the solution in the container that was not shaken or stirred.

4. Did you find the answer to your problem? Be prepared to share your results with the rest of the class.

Group 3

Required Materials

• 2 containers (baby food jars, clear film canisters, or pill bottles)
• Container of warm water
• Measuring spoon
• 2 tablespoons of copper sulfate
• Dropper or straw to drop liquid on to the slides
• 2 microscope slides
• Field microscope

Problem: You are going to be studying whether or not the amount of copper sulfate in a solution will effect crystal growth. Do crystals form better in a solution with more or less copper sulfate?

Activity Directions

Day 1

1. Label one of your containers with a 1/2 and the other one with a 1. Make sure that your name is on both containers.

2. Put 2 tablespoons of warm water in the container marked 1/2.

3. Put 2 tablespoons of warm water in the container marked 1.

4. Add 1/2 of a tablespoon of copper sulfate to the container marked 1/2.

5. Add 1 tablespoon of copper sulfate to the container marked 1.

6. Shake or stir both containers until all of the copper sulfate is dissolved.

7. Label two microscope slides, one with a 1/2 and the other with a 1. Using a dropper or straw put two drops of liquid from container 1/2 on to slide 1/2.

8. Put two drops of liquid from container 1 on to slide 1.

9. Put these two slides where they will not be disturbed so that you can observe them tomorrow.

Day 2

1. Use your Ultrascope to observe both slides.

2. Record observations in your science notebook by writing and drawing what you see.

3. Write 5 sentences about the differences between the crystals grown using the solution that contained 1/2 tablespoon copper sulfate and the crystals grown using the solution that contained 1 tablespoon copper sulfate.

4. Did you find the answer to your problem? Be prepared to share your results with the rest of the class.

BACK TO ACTIVITIES IN OPTICS

BACK TO THE TEACHER GUIDEBOOK

Questions or comments? Send us an email.

© 1995-2022 by Michael W. Davidson, the Center for Integrating Research and Learning, and The Florida State University. All Rights Reserved. No images, graphics, software, scripts, or applets may be reproduced or used in any manner without permission from the copyright holders. Use of this website means you agree to the Legal Terms and Conditions set forth by the owners.

This website is maintained by our
Graphics & Web Programming Team
in collaboration with Optical Microscopy at the
National High Magnetic Field Laboratory.

Last Modification Friday, Nov 13, 2015 at 02:19 PM

Access Count Since November 1st, 2000: 62732

Visit the websites of our partners in education: