hydrogen bonds w/ carbon

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kristinalaudis3e
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hydrogen bonds w/ carbon

Postby kristinalaudis3e » Sun Nov 15, 2020 7:38 am

why can't H make a hydrogen bond with carbon? I understand that hydrogen bonds can be made with N, O, and F because they're extremely electronegative and so they pull electrons towards them (making it partially negative), but then the difference in electronegativity of carbon and hydrogen is not significant enough to make a hydrogen bond. what is the threshold for the electronegativities to be different enough to make a hydrogen bond?

Khoa Vu 3l
Posts: 96
Joined: Wed Sep 30, 2020 9:59 pm

Re: hydrogen bonds w/ carbon

Postby Khoa Vu 3l » Sun Nov 15, 2020 8:05 am

I think it's important to keep in mind that hydrogen bonding and covalent bonding are not the same thing. Covalent bonds are intramolecular forces while hydrogen bonding is an intermolecular force. Hydrogen can still covalently bond to carbon within a molecule. However, outside the molecule, hydrogen bonding can only occur between hydrogen that has already covalently bonded to a highly electronegative atom, such as Nitrogen, Oxygen, or Fluorine (Chlorine has a similar electronegativity to Nitrogen but the atom itself is too large to form a hydrogen bond) and another highly electronegative atom, again Nitrogen, Oxygen, and Fluorine. Hydrogen bonding itself is the electrostatic attraction between the covalently bonded hydrogen and the highly electronegative atom as a result of the difference in their electronegativities. For example, the Hydrogen in one water molecule is already covalently bonded to Oxygen within the same molecule. When that Hydrogen is in the presence of Oxygen of another water molecule, hydrogen bonding will occur.

Keon Amirazodi 3H
Posts: 100
Joined: Wed Sep 30, 2020 9:59 pm

Re: hydrogen bonds w/ carbon

Postby Keon Amirazodi 3H » Sun Nov 15, 2020 4:46 pm

H can't make hydrogen bonds with carbon because the difference in electronegativity isn't large enough. Fluorine, oxygen, and nitrogen are all extremely electronegative so they can make H bonds. C is not.

Yuehan_Wu_3K
Posts: 52
Joined: Wed Sep 30, 2020 9:41 pm

Re: hydrogen bonds w/ carbon

Postby Yuehan_Wu_3K » Sun Nov 15, 2020 7:06 pm

A hydrogen bond forms between a hydrogen atom bonded to a strongly electronegative atom of one molecule and a strongly electronegative atom of another molecule. C is not an electronegative atom.

Rose_Malki_3G
Posts: 127
Joined: Wed Sep 30, 2020 10:02 pm

Re: hydrogen bonds w/ carbon

Postby Rose_Malki_3G » Sun Nov 15, 2020 7:27 pm

The difference in electronegativity between a carbon atom and a hydrogen atom is not great enough to make an interaction as strong as a hydrogen bond

Heidi Buri 2I
Posts: 50
Joined: Wed Sep 30, 2020 9:57 pm

Re: hydrogen bonds w/ carbon

Postby Heidi Buri 2I » Mon Nov 16, 2020 4:11 pm

Hi! I believe the reason hydrogen can't make a hydrogen bond with carbon is due to electronegative and bond length. Carbon and hydrogen have a very small difference in electronegativities which makes the bond non-polar. H makes hydrogen bonds with N, O, and F due to their high difference in electronegativities.


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