Hands-on Activity:
Build Your Own Molecule

In 1897 Felix Hoffmann and Arthur Eichengrün took apart molecules of salicylic acid and acetic anhydride, and put their atoms back together to make molecules of acetylsalicylic acid, our friend aspirin. Now we're going to give you a chance to play Felix Hoffmann and build your own molecules, or at least models of molecules.

Your teacher is going to provide some sets of molecular modeling kits. Your challenge is to put together a molecule of your own design. Be creative. Make it any way you like, within certain rules.

When you have made your molecule, write down its molecular formula.

Next, your teacher is going to help you figure out what the name of your molecule is. There are rules for naming molecules based on their molecular structures, so your teacher should be able to do this without much trouble.

Then, your teacher will help you draw this molecule on a piece of paper. You teacher may have to help you do this because it can be tricky drawing a three-dimensional object on a flat piece of paper.

Once you know the molecular formula and name of your molecule, and can draw its molecular structure, head for the library or the Internet and find the answers to the following questions.

1. Does your molecule exist in real life?

   If your answer is "yes," then answer the following questions. If your answer is "no," then find a molecule with a structure similar to the one you built, that does exist in real life. (Your teacher will help you with this.) Then answer the following questions about the real-life molecule.

2. Does your molecule have any other names than the one you and your teacher derived for it?

3. What is your molecule used for?

4. Is your molecule found in nature? If so, where?

5. If your molecule is not found in nature, from what materials is it made?

6. Is your molecule a solid, liquid, or gas at room temperature?

7. What is its melting point?

8. What is its boiling point?

9. Can you point to atoms or an arrangement of atoms in your molecule that gives it its properties, or makes the molecule useful?

10. Can you buy your molecule from a chemical supply catalog? If so, how much would 1 kg cost?

    The African black rhinoceros.

11. Is your molecule toxic? If so, how much of it would you need to kill an adult rhinoceros? Hint: the rhinoceros weighs 2000 kg.

    Note: We do not advocate actually using your molecule to kill a rhino. All species of rhinoceros are at risk of extinction. Why? Because they have been hunted for their horns, which are used in some parts of the world to make potions. These potions are thought to reduce fevers. The sad part is rhino horn has been proven useless as an antipyretic. Aspirin, on the other hand, is a proven fever-reducer that can be made without shooting a single rhino.