Questions tagged [hydrogen-bond]
Intermolecular force between covalently bound hydrogen atom and atom possessing a lone pair of electrons.
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Why can't ethyne form hydrogen bonds in water?
I was recently taught about hydrogen bonding and I learnt that a hydrogen atom attached to fluorine, nitrogen, oxygen or a sp-hybridized carbon (EN = 3.25) can get into a hydrogen bond with another ...
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Melting Point Order of Benzene Derivatives
Q)Compare the melting points of the following?
o-Hydroxybenzaldehyde
o-Methoxybenzaldehyde
p-Hydroxybenzaldehyde
p-Methoxybenzaldehyde
My attempt: Intermolecular H-bonding increases melting point ...
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Comparison of Strength of Hydrogen Bonds of Sulphur and Chlorine
In my textbook, the order for strength of H-bonding is given as
$$\ce{F > O > N > S > Cl}$$
I wonder how Cl has less strength of H-bonding than sulphur despite chlorine being more ...
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Why is picric acid not more steam volatile than p-nitrophenol, if intramolecular bonding results in increased steam volatility?
I understand that relative to p-nitrophenol, o-nitrophenol would be more steam volatile (as p-nitrophenol can form intermolecular hydrogen bonds), but my question lies in the fact that its volatile ...
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Why does fluorine form only one hydrogen bond, but oxygen forms two?
Oxygen forms two hydrogen bonds as it has two lone pairs. So, why does fluorine only forms one hydrogen bond having three lone pairs?
Both oxygen and fluorine have nearly the same size, so steric ...
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How can we prevent retrogradation of starch?
Are there any additives which can prevent retrogradation of starch? I have prepared 13% of starch solution along with 2% of NaCl. The results were bit better. The synthesized gel was flowable with ...
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Can Seaweed Be a Thermoplastic?
I was on the Internet, and I saw this post. This post shows a photo of thermoplastic seaweed, which I thought was impossible. `
BTW, if you're wondering what the difference is between a thermoset and ...
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Source(s) of extreme Raman scattering of FeOOH under intense laser excitation?
RRUFF's Raman spectrum of FeO(OH) as Goethite:
Bears no apparent similarity to the extreme Raman scattering of this sample of purported FeOOH under 785nm laser excitation with 100x objective that ...
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What is the effect of dissolving ammonia in water on hydrogen bonding?
Hydrogen bonding exists between $\ce{NH3}$ molecules. When $\ce{NH3}$ is dissolved in water, I know that hydrogen bonds are formed between $\ce{NH3}$ and $\ce{H2O}$ molecules. However, do the $\ce{NH3}...
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Diagram of the electric field potential around water
Is there diagram of the electric field around a water molecule. I have seen some simplifications that treat hydrogen as a positive point source and oxygen as a negative point source. But I am looking ...
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Hydrogen bonding of water molecule
When we say that energy of hydrogen bonds in liquid water is $\approx \pu{6.3 kJ/mol}$,
does it mean that if we divide this number among $\pu{1 mol} \approx \pu{6.022E23}$ molecules, the result is we ...
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Why does potassium bifluoride exist whereas bichloride does not?
Why does the reaction \eqref{rxn:R1Q} take place, but the reaction \eqref{rxn:R2Q} does not?
$$
\begin{align}
\ce{HF(aq) + KF(aq) &-> KHF2(aq)}\label{rxn:R1Q}\tag{R1} \\
\ce{HCl(aq) + KCl(aq) &...
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Can molecular hydrogen form hydrogen bonds?
Basically, I want to know if molecular hydrogen (H$_2$) can form hydrogen bonds with other molecules (CH$_4$, CO$_2$, N$_2$). I'm trying to model the mixture of these molecules with SAFT equations of ...
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If the 2 electrons of a hydrogen molecule are more likely to be found between the 2 hydrogen atoms, why does this diagram says otherwise?
So I am reading about bonding and antibonding molecular orbitals and i can't understand how does the probability diagram show that the electron density in the sigma 1s molecular orbital is greatest ...
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How heating of copper sulphate pentahydrate (blue vitriol) can be explained?
The chemical formula of copper sulphate pentahydrate, $\ce{CuSO4\cdot 5H2O}$ does not give information about its true structure because it's only an empirical formula.
It forms a network solid. Two ...
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