Hacker News Reader

Comment by blueadept111 | Hacker News Reader

Organic chemistry is the bomb. I was bored to death with inorganic chemistry, maybe because of the way it was presented, but organic chemistry seemed like suddenly being shown that all the cool stuff in the world is made of lego pieces (carbon atoms), and there's a manual for how to put them together in different ways.

I wasn't exposed to it until university, but I always thought the material would make a good intro course for high school chemistry.

View on HN

> all the cool stuff in the world is made of lego pieces (carbon atoms)

Amen. When I introduce organic chemistry, I use the Lego analogy.

I tell the students, "there are zillions of different organic molecules. What's weird is that you only get to 'play' with a small fraction of the periodic table in organic chemistry [C,H,O,N,P,S,F,Cl,Br ...]. So, how do you get 'zillions' of different molecules from a narrow set of elements?"

Then I show them a photo of several 2x2 Legos arranged as 1) a tower, 2) one-way staircase, 3) two-way staircase, 4) "circle"

Organic chem lab is awesome, too. I remember making isoamyl acetate (banana scent) with 30 other students and the whole lab smelled wonderful.

edit: I forgot. I worked with a guy who made a functioning spectrophotometer out of Lego parts and LEDs??. I think he got the idea from a journal devoted to undergraduate chemistry education.

edit2: I didn't read the entire blog post (because...super long), but I agree w/ the parts that I did read. e.g., "[Modern introductory chemistry is] ...sterile chemistry. It’s the equivalent of teaching kids scales before they learn to play a song, or insisting that kids learn grammar before teaching them how to write. It’s chemistry as rote and rules, with no joy to exploration."

A lot of the issue stems from presenting the information to students as if it were "the truth." A lot of what is presented isn't the truth--it's just a reasonable model to explain experimental data. And I think it's beneficial to explain that nuance to students. "This explanation/model works great under most circumstances, but it falls apart over here." I spent a large part of my undergrad years thinking everything I learned was gospel. And I wish my teachers had spent more time discussing model building based on experimental data.

I think it all comes down to the instructor. I took Organic the 1st time with a semi-famous professor who didn't want to be there and just sat next to an overhead projector and wrote down formulas for us to memorize. Boring! I squeaked by with a C. When I had to take it again for grad school because I failed the organic part of the entrance exams (imagine that) I had a completely different experience. The instructor obviously loved to teach and she taught us the principals as to why A+B=C rather than just memorizing. I loved that class and got an A.

Organic and inorganic chemistry are almost two separate subjects. I also took organic freshman year in college with a professor who I think probably ended up in the running for a Nobel Prize. I'm not sure he was particularly bad but it was a large lecture class, I hated organic and it was one of the first subjects I ever didn't really grok at some level, and actually somewhat changed majors because of it.

Inorganic on the other hand. I ended up getting a grad degree in Material Science which is closely related to aspects of solid state chemistry--so, yes, I liked aspects of chemistry. Just not organic.

The trouble with organic chemistry is that it's a lot harder than inorganic chemistry precisely because of the near-infinite complexities of organic molecules. If you want to teach people the basics, such as how to identify a sample or how to perform analytic chemistry (for example, work out how much of a compound you have got in a volume of solvent), you really have to start with inorganic chemistry.

On the other hand, understanding molecular bonding is much easier in organic chemistry. Inorganic chemistry mostly requires molecule-by-molecule computational solutions, whereas organic can get you quite far purely with rules of thumb. I majored in chemistry, and it was widely accepted that inorganic chemistry was "harder" because of the above.

My experience is exactly the opposite. Inorganic chemistry is mostly governed by the valencies of the elements reacting (and thermodynamics, of course) which are easily learned. Whereas organic chemistry is enormously complicated by the sizes and shapes of the molecules.

But as it turns out, you can (mostly) rely on some very simple rules of thumb to describe all those different sizes and shapes. There are only so many functional groups from which the organic zoo is built, and the most common ones (e.g. a benzene ring) are very well understood by now. On top of that, organic chemistry usually involves the low energy shells, for which sp-hybridization schemes work pretty well in describing the bonding.

In contrast, inorganic chemistry regularly involves higher-energy shells, that have much more complicated geometries and energy levels. Relativistic effects also come into play, and the end result is that you often can't even make a guess at what the molecular orbitals look like. And if you don't know what the molecular orbitals look like, you also don't know how the molecule will react with other molecules, since you don't know what the charge distribution is.

EDIT: the general attitude in my uni, also among the professors, was that the inorganic folks had a much harder time theoretically than the organic folks. As in, the inorganic might make a fancy new compound, yet have no idea how the molecule "worked". On the other hand, the organic folks had a much harder time experimentally - they would usually only have a few mg of product, whereas in inorganic chemistry you can often end up with as much as you like.

Inorganic gets very complicated very quickly. You end up dealing with Group Theory and 3D symmetry operations before you know it. And this is ignoring bio-inorganic chemistry, which is also very important.

My experience with organic chemistry was... not good in comparison. Were you a chemistry major?

Reply on news.ycombinator.com