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memorization of IR, NMR signals??

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juniper456

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TPR says to memorize the values of various IR and NMR spectra signals (for different functional groups, types of hydrogens, etc). is this really necessary? it seems like overkill to me. . .
 

Turkeyman

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EK says that for NMR, you'll find electron donating groups upfield(to the right on the NMR graph) b/c they shield the proton. You'll find electron withdrawing groups downfield (left side).

From there you can estimate...so just know your electron donating and withdrawing groups (back from when you studied benzene ring activation/deactivation/positioning
 

tank you

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for IR, u should know carbonyl stretch (1600), OH stretch (~3200)..
for nmr, u should know how to read the graph and tell # of equivalent H.
 

longhorndoc

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jtank said:
for IR, u should know carbonyl stretch (1600), OH stretch (~3200)..
for nmr, u should know how to read the graph and tell # of equivalent H.

Ditto. NMR and IR values are relatively easy to memorize for the most commonly used groups. Make cards and you'll know them in a day. It's worth knowing b/c you may get a freestanding question or freestanding like question w/ a passage asking what the value is. These are such EASY questions that I would hate to miss them due to not memorizing them. Don't stress over them though b/c you're likely to only get one question on this if even any. Good luck
 

MoosePilot

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Depends what score you're shooting for. I memorized the most important ones and needed them. If you're only going for the 30, then you might spend your time more productively elsewhere.
 

Economist

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If you've taken 2 semesters of orgo and/or orgo lab, you should have enough memorized already. You really only need the major functional groups for IR and proton NMR. And as a previous poster said, you should understand splitting.
 

MoosePilot

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Economist said:
If you've taken 2 semesters of orgo and/or orgo lab, you should have enough memorized already. You really only need the major functional groups for IR and proton NMR. And as a previous poster said, you should understand splitting.

Ok, this one probably varies by the person. I hope, or else I'm just weird. If I don't have to memorize something, I'll almost never memorize detail just randomly. Like the IR thing. If I know I'm always going to have access to charts, I'll never have it in memory unless I just work with it *way too often*.

Anyone else like that? I can memorize it just fine if I need to (although it's already gone again from last April), but I don't do it naturally.
 

virilep

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for the time u spend readng this thread and the updates, u could have already memorized it.... bust out that whiteboard.
 
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juniper456 said:
TPR says to memorize the values of various IR and NMR spectra signals (for different functional groups, types of hydrogens, etc). is this really necessary? it seems like overkill to me. . .
nope



you should be able to pick off a methyl group or an aromatic ring on NMR or a ketone or hydroxy group on IR, but not much else.
 

Shrike

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I saw a free-standing question on my August 2004 test that required knowing one of the numbers, I forget which one. Demoralizing for those of us who look at the MCAT as a reading comprehension test.

Shrike
TPR physics, verbal, bio (and unfortunately not chemistry)
 
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