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Dec 13 2011 12:16am
it was fun for me, but I was always strong in the subject. The memorization comes down to semantic encoding and just spending enough time reading the text/notes and doing practice problems (2-3 hours study for every 1 lecture-hour)

the hardest part about organic chemistry is learning to draw and understand diagrams written in 'chemistry language' like lewis structures, newman projections, fischer projections.

past the difficulties, i found how alot of the knowledge from orgo is applied in modern industrial processes in the real world, which i found really interesting
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Dec 13 2011 01:41am
Quote (cialda @ Dec 13 2011 12:56am)
i guess my inorganic was less intense than that :O
we went over pi backbonding slightly, but the course was 1 semester and it was "inorganic chemistry: chemistry across the periodic table" or something like that. we just went over reactions of the entire periodic table. /e * we did go over some orbital over lap for a few chapters but that was it. the way you make it sound, it seems you went much deeper. also that class was one of my favorites because of the accompanying lab. we actually had fun labs.*
also, did you go in depth in organic for orbital overlaps and all that? we mainly stayed to just electron pushing diagrams mainly in organic at my school.


There's the inorganic you take before organic chemistry, which is mainly the basics of physical chemistry with some brief details on electron orbitals and overlaps, spin states, and ground state configurations, and then there's the inorganic you take after organic, i.e. hell. I don't think there are many schools that have the time to teach any more than electron pushing mechanisms, which is what we basically did in orgo.

I learned an asston of things in my intermediate inorganic chem class though. Even things you thought that were obvious, such as why water is a linear molecule as opposed to a bent molecule are things that are expounded upon in greater depth:




In linear H2O the O 2s and O 2pz orbitals could form sigma bonds with H while the O 2py and O 2px orbitals would be nonbonding. In the bent H2O the 2s sigma and the 2px orbital are allowed to hybridize which lowers the energy of the 2px orbital and results in only one non-bonding orbital (O 2py). In other words, the hybridization that happens between the 2s and 2px orbitals allows for one of the lobes in the pi orbital of the oxygen (in the middle of H2O) to be much bigger and results in a greater overlap with all the two sigma orbitals of the hydrogens around it (when the water molecule is bent). When the molecule is linear, the 2px orbital is in an orientation that makes it unable to bond with the s orbital of the hydrogens, and the energy of the orbitals that do bond are higher because the electron overlap with the sigma bonds between s orbitals aren't as great.


It's conceptualizing some of these concepts and explaining them properly that made the class fairly challenging; what I just showed you was a fairly simple MO, just something i thought was neat, the class grew exponentially harder later on with much more abstract and difficult concepts. But as you can see, it's very different from organic in that it's far from straight memorization, there gets to be a good amount of reasoning that's necessary to understand the concepts.

This post was edited by Nihlathak on Dec 13 2011 01:45am
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Dec 13 2011 02:20am
Quote (Nihlathak @ Dec 12 2011 08:40pm)
Organic 1, 2, and lab are all joke classes compared to what came after them at my school. You really don't work with many atoms in organic (and you're limited to the s and p shells and their interactions mostly); shit gets insane when you work with mechanisms involving inorganic and organometallic compounds, and then learn how to draw their MO's and how exactly all their electrons overlap to form bonds, what happens to MO energy levels and the lines depicting what electrons contributed to what molecular orbital when the molecule distorts in a certain way, what happens to the energy levels and how the electrons overlap when hybridization takes place, etc. Hell, even knowing how to draw the correct MO with the correct lines, the correct bond types, and energy levels of a molecule as seemingly simple as CO2 can be a bitch when you're first starting out.

You can go through orgo simply by sheer memorization, but you were literally fucked in my intermediate inorganic chemistry class if you didn't understand the "whys" and "hows" of everything from everything to the implications of pi backbonding...

http://www.ilpi.com/organomet/gifs/alkyneorbitals.gif

...to the reasons for why the eg and t2g d orbital interactions are higher or lower in energy in the presence of certain circumstances:

https://encrypted-tbn0.google.com/images?q=tbn:ANd9GcQoGnJ4JJ1jv-7aXAhp7f7q1z4kHpueqla1hwbQsEOtefqVXsqg4A


I wish everyone who bitched about orgo had to take this class.


my school is exactly the opposite. the inorganic and transition metals classes are super easy and ochem is whats tough
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Dec 13 2011 08:31am
Quote (Nihlathak @ Dec 13 2011 01:41am)
There's the inorganic you take before organic chemistry, which is mainly the basics of physical chemistry with some brief details on electron orbitals and overlaps, spin states, and ground state configurations, and then there's the inorganic you take after organic, i.e. hell. I don't think there are many schools that have the time to teach any more than electron pushing mechanisms, which is what we basically did in orgo.

I learned an asston of things in my intermediate inorganic chem class though. Even things you thought that were obvious, such as why water is a linear molecule as opposed to a bent molecule are things that are expounded upon in greater depth:

http://htmlimg1.scribdassets.com/an50d8o5cozopz/images/5-dfc85c66b2/000.jpg


In linear H2O the O 2s and O 2pz orbitals could form sigma bonds with H while the O 2py and O 2px orbitals would be nonbonding. In the bent H2O the 2s sigma and the 2px orbital are allowed to hybridize which lowers the energy of the 2px orbital and results in only one non-bonding orbital (O 2py). In other words, the hybridization that happens between the 2s and 2px orbitals allows for one of the lobes in the pi orbital of the oxygen (in the middle of H2O) to be much bigger and results in a greater overlap with all the two sigma orbitals of the hydrogens around it (when the water molecule is bent). When the molecule is linear, the 2px orbital is in an orientation that makes it unable to bond with the s orbital of the hydrogens, and the energy of the orbitals that do bond are higher because the electron overlap with the sigma bonds between s orbitals aren't as great.


It's conceptualizing some of these concepts and explaining them properly that made the class fairly challenging; what I just showed you was a fairly simple MO, just something i thought was neat, the class grew exponentially harder later on with much more abstract and difficult concepts. But as you can see, it's very different from organic in that it's far from straight memorization, there gets to be a good amount of reasoning that's necessary to understand the concepts.


ya those were the MO that we had to learn as well. i cant remember if it was at the start or the middle of the class though that we learned those. either way, we may have gone only slightly more in-depth than the picture you posted for MOs. Also, we did use pi backbonding for transition metal binding, but we rarely drew out the MO for binding in this situations. I guess though at my school, it seemed easy since we could leave out these MO for most of the problems, however it was one of the funnest by far for laboratories. We were able to make nickel nanowires and look at them with a SEM. Also, we did something with a little LED, gah cant remember exactly what we did ;'/ . Another thing i found interesting was we over one powder compound that when breathed CO2 on it, it could produce oxygen and H2O i believe, but for the life of me i cant remember what it was.

As for differences, i do agree that organic is more memorization than inorganic, but i really do not think there was too much memorization in organic. i guess i dont know how organic was for you, but second semester was mainly just electron pushing diagrams, telling what the product of a reaction was going to be, or they would give you a reactant and a product and you have to put in the other reactants or show step by step how to get there. Those, imo, would be less memorization excluding some of the necessary "side" reactants since we had to know what catalyst they used and type of solution. For the others though, if you knew the more reactive parts and what the side reactants would do, you could reason most of the problems.
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Dec 16 2011 01:41am
I too found inorganic much more difficult. The subject I took was called chemical biology so the focus was obviously geared towards biological systems. However, the bioinorganic section was extremely challenging. One of my final exam questions involved interpreting pages of EPR and UV-VIS spec data, deducing the structure of the metallo-proteins (based on the EPR/UV-VIS data and hard/soft ligand tables), then inferring which would be a more efficient electron transporter at a certain pH etc. You cannot rote learn this stuff.

The organic section was pretty much rote learning electron pushing. Aside from the mechanistic enzymology module which was way too many steps to rote learn (for me at least). Having an understanding of how/why certain AA residues in the active site of the enzyme would catalyse the reaction was essential.

To the OP: As others have mentioned, you will benefit much more from understanding why reactions occur rather than rote learning where to push the electrons. I neglected this in one of my earlier chem classes at uni and it only gets harder. If you put the work in to really understanding why the reactions proceed in the manner they do, I'm sure you won't have any problems - particularly because you said the subject interests you in the first place.

Good luck.

This post was edited by lims101 on Dec 16 2011 01:46am
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Dec 16 2011 04:32am
Quote (lims101 @ Dec 16 2011 06:11pm)
I too found inorganic much more difficult. The subject I took was called chemical biology so the focus was obviously geared towards biological systems. However, the bioinorganic section was extremely challenging. One of my final exam questions involved interpreting pages of EPR and UV-VIS spec data, deducing the structure of the metallo-proteins (based on the EPR/UV-VIS data and hard/soft ligand tables), then inferring which would be a more efficient electron transporter at a certain pH etc. You cannot rote learn this stuff.

The organic section was pretty much rote learning electron pushing. Aside from the mechanistic enzymology module which was way too many steps to rote learn (for me at least). Having an understanding of how/why certain AA residues in the active site of the enzyme would catalyse the reaction was essential.

To the OP: As others have mentioned, you will benefit much more from understanding why reactions occur rather than rote learning where to push the electrons. I neglected this in one of my earlier chem classes at uni and it only gets harder. If you put the work in to really understanding why the reactions proceed in the manner they do, I'm sure you won't have any problems - particularly because you said the subject interests you in the first place.

Good luck.



Thanks, I appreciate all the advice and information :)
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Dec 16 2011 10:28pm
Personally I loved organic chemistry. I walked into school as a bio major and my favorite class was organic chemistry. If I wasnt pre-dental I would probably become a chem major (curently going to be minoring in it) and probably get a phd in organic chemistry. I currently took 1 year of organic chemistry, TA'd organic chemistry 1 this current semester and will be TA'ing organic chemistry 2 next semester. Also just took organic chemistry lab.

If your good at figuring out puzzles then you would be good at organic chemistry.
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Dec 18 2011 05:51am
I wouldn't suggest it.
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