COMPLEX MOLECULES

OBJECTIVE:
Identify the similarity of different complex molecules by their structure.

BACKGROUND:
Benzene is an extremely prominent chemical substance.  Benzene consists of a cyclic arrangement of 6 carbon atoms with a single hydrogen attached to each carbon.  All the bonds are at 120 degrees. 

Benzene and many other related molecules are referred to as aromatic hydrocarbons because some of the compounds related to benzene possess a spicy fragrance.  Many aromatic substance however do not have a pleasant smell. 

Some benzene based hydrocarbons are used as sweeteners both artificially and naturally.  Natural sweetener, glucose, have been replaced by low calorie artificial sweeteners.  All of these have a benzene ring as a component.

 PROCEDURE:
There are two parts to this activity.  First have the students construct a benzene model by using one pipe cleaner and 6 beads per student.  First have them construct what it should look like on their lab sheet. 

Second part is to cut out the models and then put the rings together.  These are not as easy as they seem.