Questions tagged [hydrogen-bond]
Intermolecular force between covalently bound hydrogen atom and atom possessing a lone pair of electrons.
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Why C-D bond is stronger than C-H bond though D is more heavier than H? [duplicate]
I read that as the atomic mass increases, the bond length increases and hence the bond strength decreases. Then why C-D bond is stronger than C-H bond?
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Can we decouple electrostatic force from hydrogen bonds?
The nature of hydrogen bonds is an intriguing question. According to this post, hydrogen bonds are made primarily of electrostatic force with a small contribution of electron transfer to the ...
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Reasons of ethanol's and ethanethiol's complete solubility and low solubility in water respectively
Suggest an explanation for the observations that ethanol($\ce{C_2H_5OH}$), is completely miscible with water and that ethanethiol ($\ce{C2H5SH}$) is soluble only to the extent of 1.5 g per 100 mL of ...
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Dipole-dipole vs London dispersion forces for deducing melting and boiling points
To determine the melting and boiling points of compounds, London dispersion forces are typically compared. However, why are the polarity and dipole-dipole forces ignored?
For instance, $\ce{HI}$ has a ...
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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 ...
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Are hydrogen bonds between two hydroxyl groups stronger if one is deprotonated?
Hydrogen bonds can form between two hydroxyl groups. Is the hydrogen bond stronger if one of the groups is deprotonated?
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Do CHF3 and acetone form a hydrogen bond?
I haven't been able to find a reference confirming that fluoroform forms hydrogen bonds with acetone. Do they?
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What is the reason for the boiling point of benzene-1,4-diol being higher than that of benzene-1,3-diol?
What is the reason for the boiling point of benzene-1,4-diol being higher than that of benzene-1,3-diol?
Both have hydrogen bonds. I think it is due to quinol's symmetry but can't point out exactly ...
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Hydrogen Bonding in case of nitro group [closed]
In many different cases of Nitro group I have seen that only one oxygen atom is particularly used for hydrogen bonding but not the other one.But I guess both the bonds should be polar and hence show ...
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Hydrogen Bond Length and Lattice Density [closed]
The subject of the density of solid water is discussed on Physics Stack Exchange in this post.
In the post, it is said that..
the way the molecule is angled ensures that a specific (energetically
...
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Would the hydrogen-bonded polymer hexaamminecobalt(III) hexakis(trifluoromethyl)cobaltate(III) be soluble in water?
It is clear that both the hexaamminecobalt(III) ion and the hexakis(trifluoromethyl)cobaltate(III) ion are both low spin (the former is already low spin, and the trifluoromethyl ligand is clearly ...
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Does ammonia exhibit hydrogen bonding in its gaseous state?
I was reading the properties of ammonia in my book (NCERT Chemistry Part I, Textbook for Class XII)
where it was written :
In the solid and liquid states, it (ammonia) is associated through hydrogen ...
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Out of tropolone and tropone, which is more soluble in water?
According to me tropolone has intramolecular H-bonding, so extent of H-bonding with water will decrease and thus, will be less soluble.
Tropone (Cyclohepta-2,4,6-trien-1-one):
Tropolone (2-...
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Which compound of these following have electrovalent, covalent, coordinate as well as hydrogen bond?
Which compound have electrovalent, covalent, coordinate as well as
hydrogen bond ?
A) $\ce{[Cu(H2O)4]SO4.H2O}$
B) $\ce{[Zn(H2O)6]SO4.H2O}$
C) $\ce{[Fe(H2O)6]SO4.H2O}$
D) $\ce{[Fe(H2O)6]Cl3}$
Answer ...
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Why hydrogen bonding in some acids make them a stronger acid when it is present even before deprotonation?
If we take the example of salicylic acid, hydrogen bonding is present in the acid as follows:
Even after deprotonation, it has intramolecular hydrogen bonding as follows:
My question:
p-...
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Why is Maleic Acid more soluble in water than its trans isomer Fumaric Acid?
My teacher taught me that compounds having intramolecular H-Bonding are relatively less soluble in water as they will not involve in H-Bonding with water appreciably while those able to do ...
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Comparing the boiling points of common organic molecules
The order I was provided with is(comparing molecules of similar molecular mass from each);
alkanes< ethers< esters< aldehydes< ketones<< alcohols<< carboxylic acids<< ...
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Which of the following compounds possess more than one percent enol content? [closed]
Which of the following compounds possess more than one percent enol content?
I understood that stability of enols are dependent on the hydrogen bonding in the compounds. But here, what is the ...
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What happens when hydrogen bonds stretch?
I'm researching about the Mpemba effect and I came across an explanation saying that the effect occurs because at higher temperatures, the hydrogen bonds between the water molecules stretch and store ...
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How do point mutations affect complementary base-pairing and widths of the nucleotide pairs?
Point mutations are divided into two categories: transitions and transversions. Since point mutations only occur during DNA replication (an integral process of both mitosis and meiosis), the mutated ...
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How to interpret this formula about hydrogen bond energy
I want to evaluate some chemistry related formulas, which I don't understand.
In proteins, hydrogen bonding often occurs between the oxo group = O oxygen of one amino acid and the α-amino group (N − H)...
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