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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What is the determining factor between two potential bond candidates? [closed]
Say you have a vacuum (imaginary, of course) with three hydrogen atoms, how do we determine which two will bond and which one will be left out? If the same energy is present (equally) for the entire ...
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How to calculate absolute charge of a protein [closed]
My understanding is that hydrogen bonds formed by proteins require the NH2 / COOH to be neutral. Hence to find out when the hydrogen bonds are the strongest will depend on the absolute charge of the ...
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Hydrogen bond in water vapor [closed]
As the temperature increases and liquid water changes to gas, are ALL the hydrogen bonds broken or they are just weaker?
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Can flaxseed (linseed) oil undergo hydrogenation?
I'm curious if it's possible to chemically hydrogenate flaxseed (linseed) oil. I've never seen it in hydrogenated form. Given its quality as an excellent wood protectant, I figure it would be easier ...
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Difference between number of hydrogen bonds formed and number of hydrogen bonds in a molecule [closed]
I would like to know how to count the number of hydrogen bonds formed in a molecule and the number of hydrogen bonds that a molecule has. For example, water forms two hydrogen bonds with its two ...
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Can hydrogen fluoride form three or more hydrogen bonds? [duplicate]
As far as I know, each $\ce{HF}$ molecule has two hydrogen bonds, one formed by its hydrogen atom and one which the $\ce{F}$-atom forms with hydrogen atom of a third $\ce{HF}$ molecule.
In other ...
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intramolecular h-bonding in maleic acid
While studying organic chemistry, I came across two practice questions given by my professor:
Compare the acidic strength of:-
Maleic acid and Fumaric acid
o-nitrophenol and p-nitro phenol
And the ...
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How can we explain solubility of hydrogen sulfide in water?
On my most recent high-school chemistry exam I had a longform question where I was supposed to compare the solubilities in room-temperature water under normal pressure of a few molecules. According to ...
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Comparison of hydrogen bond strength
Consider the following sets of H-bonds:
$$
\begin{align}
&\text{P:} &\ce{-O-H\bond{....}N} \\
&\text{Q:} &\ce{-O-H\bond{....}O} \\
&\text{R:} &\ce{-N-H\bond{....}N} \\
&\...
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Dissolution of sugar in water and its temperature dependence
As far as I can remember, I was taught in 6th grade that warm water would dissolve sugar with greater ease than cool water. In 11th grade, I was taught that Hydrogen Bonding is the reason behind ...
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What drives hydrophobic effect/interactions? (multiple choice question)
Water molecules cause hydrophobic interactions because
A- they can disrupt surfaces with no hydrogen bonds.
B- they prefer to
be close to hydrophobic surfaces
C- they are restricted in their rotation ...
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DI water vs. Tap water in ethanol-water and salt phase change reaction
We did a very simple lab like one you would do in highschool showing that you can seperate the phases of water and ethanol using salt. As simple as it sounds, we could not get it to work no matter ...
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What are the necessary conditions for formation of a Hydrogen Bond?
Usually Hydrogen bonds are associated with N,O,F as the atoms involved. In some cases OH---Cl bond is observed as in case of o-chlorophenol.
According to the updated IUPAC definition a Hydrogen bond ...
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Why does steam store large amounts of energy?
We all know that steam can be used to perform mechanical work and steam has a high capacity for energy storage. But why does steam have such high energy capacity?
I tried searching for answers on the ...
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Does hydrogen bonding affect the structure of a molecule?
We know an individual molecule of $\ce{H2O}$ has a bent structure, but if we consider a volume of water, then there are many molecules having hydrogen bonding with each other. Due to this, does the ...
