Molecular Mechanics

During the first week of the Fall Semester that all the Organic Chemistry lab sections meet, the students do a molecular modeling exercise. What makes Organic chemistry different from most of the other courses the students have taken is the constant reference to molecular structures when talking about chemical properties and reactivity. Organic chemistry takes a fair amount of spatial skills. My secret belief is that people who have use spatial skills in their careers such as sculptors and car mechanics would do well in organic chemistry. In any case, students need to be impressed that molecules are spatial objects that can be manipulated in three dimensions (just like car parts). I have bought a few molecular model kits over the years – the plastic ones and I use those kits for this activity. Interestingly, very few students complete the exercise while making every single model. Usually, once they get the hand of drawing the structures on paper they go ahead and write them without bothering to construct the models. After all, they get graded on their drawings and not their models! Here is a pdf of this activity. There are a few molecular model activities out there. There is a recent article in the Journal of Chemical Education entitled, “A Laboratory Experiment Using Molecular Models for an Introductory Chemistry Class” by Shahrokh Ghaffari. In addition; JCE has had “feature molecules” each month that are shown as molecular models.