All Questions
Tagged with hydrogen-bond physical-chemistry
18
questions
-4
votes
1
answer
34
views
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 ...
5
votes
2
answers
2k
views
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 ...
0
votes
1
answer
186
views
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 ...
0
votes
0
answers
19
views
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 ...
2
votes
1
answer
210
views
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 ...
-1
votes
2
answers
155
views
If acid releases proton then how can a proton react with another proton to form hydrogen gas? [duplicate]
As we know that acid releases proton (H+ ion) when dipped in water hydrogen has a proton and electron only . To form H+ hydrogen releases 1 electron and it becomes proton. But when Acid reacts with ...
3
votes
1
answer
2k
views
How does the entropic force arise within the hydrophobic effect?
I know that the hydrophobic effect is usually explained by the entropic effect originating from the disruption of hydrogen bonds between molecules of water and the nonpolar substance. The hydrogen ...
-2
votes
1
answer
436
views
How hydrogen molecule is formed? [closed]
How two hydrogen atoms come close to form a bond ? Textbooks refer to a potential energy diagram but what i cant understand is what is this potential energy if the atoms are neutral . How they come ...
0
votes
1
answer
2k
views
Why is the melting point of hydrogen fluoride lower than that of ammonia?
The melting point of hydrogen fluoride is -83.6°C, as compared to that of ammonia, which is -77.73°C. How does this make any sense?
Both hydrogen fluoride and ammonia show hydrogen bonding, which "...
7
votes
1
answer
642
views
IChO problem involving the condensation point of NF3, NHF2, NH2F
This is a problem from the 2016 International Chemistry Olympiad (IChO):
Which of $\ce{NF3}$, $\ce{NHF2}$, and $\ce{NH2F}$ condenses at the lowest temperature?
The answer book says that it is $\ce{...
4
votes
1
answer
35k
views
Why is the boiling point of water and ammonia so different?
Boiling point of water is 100 degrees Celsius, while boiling point of ammonia is minus 33 degrees Celsius, which makes 133 degrees difference. Now when we discuss value of boiling point, we also say ...
4
votes
0
answers
79
views
Tools for investigating hydrogen bonding
What would be the best tool to investigate local molecular organization in liquid mixtures due to hydrogen bonding?
For example, I might want to look at how water molecules hydrogen bond to PNIPAM vs ...
11
votes
1
answer
690
views
How to simulate surface tension?
I am trying to create a water drop simulation for measuring hydrophobicity of surface. I don't know how to simulate the contact angle which is related by younges equation to the surface tensions for ...
5
votes
1
answer
189
views
Theoretical model for the hydrogen bond
I am curious how, from the perspective of quantum chemistry, the hydrogen bond is modeled. In particular I am interested in using such a model to estimate the amount of energy released per $\ce{H2O}$ ...
3
votes
1
answer
5k
views
Volatile nature due to hydrogen bonding
Why does intramolecular hydrogen bonding make an organic (or possibly inorganic as well(?)) compound volatile.
What I think is that it might be due to decrease in the solubility of the compound as ...
10
votes
1
answer
16k
views
How does intramolecular hydrogen bonding cause the molecules to be separated from each other?
I learnt about intramolecular hydrogen bonding today, which occurs between molecules such as ortho-nitrophenol. What I was told is that in case of intramolecular bonding, the molecules separate from ...
38
votes
2
answers
30k
views
What exactly is hydrogen bonding (and does it really need fluorine, oxygen, or nitrogen)?
I'm not satisfied with the rationale for the intermolecular attraction known as hydrogen bonding. In my book, it states that
Hydrogen bonding is a special type of intermolecular attraction between ...
6
votes
3
answers
40k
views
Strength of intramolecular vs intermolecular hydrogen bonds
Why are intramolecular hydrogen bonds weaker than intermolecular hydrogen bonds?