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- Aug 11, 2010
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is hydrogen bonding only limited to F, O and N? or can other elements hydrogen bond as well but very very very weakly (like P, S, Se, Si, C and such?)
thanks!
thanks!
+1 +1 +1Hydrogen bonding is FON! (and keeps everything alive)
I'm guessing this wasn't an AAMC material question? In any case hydrogen bonds involving chlorine and sulfur do occur but are typically not discussed at the level of MCAT chemistry.okay because there was a question that asked which of the following has the weakest hydrogen bond: HF, H2O, H2S, or HCl. I put H2O since Sulfur and chlorine do not hydrogen bond but the answer was H2S since sulfur made very weak h-bonds. so should the answer have been H2O then?
and thank you for that IR tip!
My problem with this advice, and really with this question, is that there isn't a clear expectation of the knowledge level expected on the MCAT. Typical general chemistry courses discuss only hydrogen bonds involving fluorine, oxygen, and nitrogen, and all review material I've seen (TBR, TPR, Kaplan, EK) has recommended approaching such questions from a level that does indeed limit hydrogen bonding to these hydrogen bond acceptors. The AAMC PS content outline does not specify regarding this matter. In any case I can imagine two approaches to the question at hand:In this case, you should use process of elimination--you know that HF and H2O both have very strong hydrogen bonds, so those two answer choices are out. Then, you are left with H2S and HCl. Among the two, Sulfur is the least electronegative, so it will pull electrons away from the hydrogen the least--creating the weakest hydrogen bond.