Tuesday, January 15, 2008

On the basic nature of Organic Chemistry

During the first day of my Sophomore Organic Chemistry class (the second semester portion) I waxed philosophical. We were reviewing first semester stuff just to get everybody's brain (including mine) back into gear.

Occasionally, I like to put this class into some sort of context for my students. Organic Chemistry at this level can be bewildering. Organic Chemistry can be bewildering at ANY level, but I've noticed that at about two-thirds of the way through the first year, students start to get really weighed down by the subject.

This course is the typical 2nd year Organic Chemistry course. It covers all of the basics, from nomenclature to physical organic to reactions etc.... We cover a ton of material but only cover the tip of the tip of the iceberg.

I try to put this course into context using an analogy. Doing Organic Chemistry is like learning to write.

To learn to write, one must learn about all of the grammatical pieces and what purpose they serve (i.e. nouns, verbs, adjectives, prepositions etc...).

Students first learn what a noun is and how a verb makes it "do" something. The boy walked.

After mastering that, the student can add prepositional phrases. The boy walked into the store.

Eventually, through the employment of many different grammatical elements, the simple sentence can convey a great deal of information. The young boy slowly walked into the pet store and bought a dozen goldfish.

With the proper practice, this sentence can be combined with others to create a paragraph. Eventually, a number of paragraphs can be combined to form a story. The quality of the story can certainly vary, and writing a good story requires great skill.

This process is the same in organic chemistry. Right now, I am teaching my students how to use the nouns and verbs of organic chemistry. Eventually we will be able to use prepositional phrases. However, even though we cover a ton of material in this class, we will not get beyond that stage.

That is unfortunate (albeit, necessary). In my Advanced Organic Chemistry course we finally get to "read" a story: a total synthesis. Towards the end of that class, they learn to write their own paragraphs.

It is usually in grad school where they will get the chance to write a story (i.e. a total synthesis) on their own (or at least contribute significantly to one).

There is great beauty in organic chemistry. Sadly, it is hard to see during the early days of ones education. I never truly appreciated organic chemistry until Advanced Organic Chemistry during my senior year. There we read the "stories" and I was greatly impressed.


Ψ*Ψ said...

Mmmm. Sophomore organic...One of the first things I took in college that I didn't completely suck at. Advanced organic kicked my ass, though. Somehow I still loved it.

Liberal Arts Chemist said...

Yeah, it is a pedagogical form of the Aufbau Principle. My students are so poorly taught written language skills that the analogy would be lost on many of them. I always tell my students that the intention of an undergraduate DEGREE is to get the student to the point where they can have an intelligent conversation about chemistry. The two analogies that I use are:

Learning math: memorization - general principles - exceptions - higher concepts

Moving to a new city; memorization (names, addresses, buildings and streets) - knowing the "lay of the land" - taxi driver

I find the students "get" the new city analogy better. There are things you just simply have to know when you move to a new city and you either memorize them or learn them by repeated use. Then again with even a limited knowledge of a new city you can survive if you speak the langauge, can read a map and are willing to ask for help.

Godspeed on your new semester

milkshake said...

One thing I remember distinctly when trying to learn German as a kid (and being thoroughly repulsed by it) is that even the most logically-organised expose on grammar is worthless if you don't use the knowledge for anything that you like.

So I suggest that you interspese your organic chem nomenclature with stories about "lifes of molecules" - how cyclohexane looks and smells and how it compares to benzene and hexane etc. You don't need to teach them any real synthesis or mechanisms at this point - just tell them some chemistry stories to draw their interest.

Nothing kills interest in chemistry interest faster than starting with electron configuration of elements. Kids want to see sodium burn and iodine make purple vapours rather than hear about closed shel phenomena and "1s-2s-2p-3s-3p-4s-3d". Sure you want to teach that too but not on the first class.