Shapely Models!

Iroduction| Invitation| Exploration| Explanation| TakingAction | Conclusion



Doctors and scientists around the world are trying to develop new drugs to treat AIDS. Read about 'How to Ease Suffering' and 'Give Hope' to those who are in pain. abcnewssegment on availability of aids See how these professionals rely upon molecular shape to design new drugs in the treatments of disease.


  • Using VSEPR, determine how the shape of a molecule is predicted.
  • Relate the molecular shape of a small molecule to its polarity and properties using water as an example.
  • Understand how polarity determines molecular shape in large molecules using carbon compounds as an example.
  • List practical applications of molecular modeling in disease control.


  • Material you will need:
  • 5ml plastic pipettes, tubing, 4 clamps, (4) 500 mL beaker, graduated cylinder, triple-beam balance scale, thermometer, ice tray, time, magnifying glass
  • 1/8 in foam board, an exactoknife, one-hole paper punch, twist ties, assorted magic markers, a meterstick.
  • plastic atomic model kit


  • Imagine discovering invisible worlds. Worlds that cannot be seen by the naked eye. Worlds that contain the secrets of the universe. Secrets which our civilization needs to uncover in order to survive. Imagine yourself as an investigative scientist, one who is dedicated to finding the shape of a wonder drug, needed by your generation, for the cure of a deadly disease such as AIDS.

 Exploration #1

 Your team is going to investigate Molecular Models. How these models are formed and how they impact medical research.

You will begin by:

1. You will find the materials to set up the molecular models for the wonder drug in your research kit. Use the materials and instructions located there to find how to assemble the basic molecular models needed in order to begin the research. Do this research first. In order to keep track of these molecular shapes make sure that you make at least one digital photograph of your investigation, and load it onto your work station computer. Seek help if you are not sure how to do this, as well as copy images from the Internet. Write a brief summary of your research and post it on the project bulletinboard.

2. After building the basics, see how other scientists are using molecular shapes to discover new drugs in the treatment of AIDS.

Exploration #2

To understand why water has such special properties, however, we must examine it at the atomic level. Water is an example of a compound. The density is a constant ratio of mass to volume. Ice floats on water because ice has a lower density than water. Ice is less dense than water because it contains fewer water molecules in a given amount of space.

You will begin by:

1. Determining the density of water and ice.

2. Perform the water experiment from the handout provided.

3. Fill in your analysis results on the appropriate Tables. Make sure all of the graph axes are labeled.

4. Each group will share their results with the class as part of the discussion.

Exploration #3

Carbon has four electrons in its valence shell(outershell). Since this energy shell can hold eight electrons, each carbon atom can share electrons with up to four different atoms. Carbon can combine with other elements as well as with itself. This allows carbon to form many different compounds of varying size and shape.

You will begin by:

1. Investigating the bonding ability of carbon by building a model of a fullerene, a recently discovered class of compounds.

2. You will find instructions for building the Icosahedron in your research kit. The size is up to you, but make it visiblewith a minimum size of no less than five inches.



Making Models

Molecular Models


After answering the questions below, make a chart showing your data for each exploration. You will share and exchange information with other groups in the class through oral presentations.




Key Questions




Model Making Questions:

1. What shape does the water molecule have?

2. What are the bond angles in a tetrahedral shape molecule?

3. Give an example of a tetrahedral shape molecule?

4. What shape has bond angles of 120o ?

5. Give an example of a molecule with the shape you described in #4.

6. What two basic patterns form your icosahedron model?

7. Why do you think carbon is a good choice for designing new drugs?

Research Questions:

 1. What chemical elements would medical nanorobots be made of?

2. How would chemical agents (e.g. AZT-drug) be transported and delivered to a target cell?

3. What would be the biggest benefit to be gained for human society from nanomedicine?  





  • Write a letter to a congress person, encouraging fiscal support of nanomedicine funding.
  • Read more information on AIDS.
  • Take part in or establish a chat room on AIDS.
  • Collect different Internet sites on molecular shapes, make a log and send this information to other students.


 Hopefully you have gained some new insights into molecular shapes and have gotten an appreciation for the development of new drugs. For further research you may check other websites created by other researchers, such as Richard Feynman.


Contact: JackHassard for questions orcomments.