Which H-bonds are more strong? between F,O,N?

[inaccensa]

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EK says that amines have lower bp than comparable alcohols, why?

 

[loveoforganic]

Worse balance of electron pair/proton donation.

 

[inaccensa]

so there is a difference in the strength of the H-bond. Since fluorine is the most electronegative, i guess F-H should be more strong. Nevertheless, this doesn't explain the high boiling pt of alchols

 

[Evergrey]

so there is a difference in the strength of the H-bond. Since fluorine is the most electronegative, i guess F-H should be more strong. Nevertheless, this doesn't explain the high boiling pt of alchols

The OH group forms H-bonds better than NH2 -- it is more electronegative and has two lone pairs as opposed to an amine's one.

I'm not really sure about why HF has the lowest BP of the three though..

Edit:

Did some more looking into it.

HF apparently forms very strong H-bonds, but I think the geometry of the H-bonds (linear ONLY) and molecular weight are a factor reducing its bp below alcohols/water.

Amines/ammonia in general don't form particularly strong H-bonds, since they only have one lone pair.

 

[loveoforganic]

The reason the amine hydrogen bonds are weak is because they're hydrogens are hardly protic. The reason amines have lower boiling points than alcohols is because they for the above reason and that they form only one hydrogen bond per molecule as opposed to two in alcohols.