All Questions
50
questions
2
votes
0
answers
82
views
Why does $\rm{H_2 O}$ have 12 degrees of freedom?
I know there will be 3 translational D.O.F. and 3 rotational D.O.F., and it can have 4 vibrational D.O.F. (one potential and one kinetic) for each O-H Bond. But from where does 2 more D.O.F. come from?...
- 41
2
votes
2
answers
74
views
Can latent heat exist when both phases cannot exist at same temperature?
This is my understanding (please tell me if i am going wrong anywhere):
During phase change (i.e. ice melting into water) the molecules absorb heat, gain more random kinetic energy, and spread apart (...
0
votes
6
answers
149
views
Conservation of water?
I know that water can exist in various states (liquid, solid, ...) and can be in various places (clouds, oceans, ground, ...). What I want to know is whether or not the total number of water ...
-3
votes
1
answer
228
views
Why isn’t $\rm H_2 O$ a primordial element? [closed]
We’re told the universe was very hot and energetic immediately after the Big Bang, and just shows H2O was present early on. Yet, it is not considered to be a primordial element. Why is that?, and what ...
8
votes
4
answers
5k
views
Since water is a molecule, can the aerosol sprayed through double slit form interference pattern?
A water molecule is made of 1 oxygen atom and 2 hydrogen atoms, so it is very small, like quantum scale small. So if I accelerate a bunch of these water molecules through the double slit using a spray ...
- 13k
0
votes
0
answers
41
views
How many degrees of freedom does the water molecule have? [duplicate]
This is mainly a question about molar heat capacity. I've read many different values for the degrees of freedom of water, for example f = 12 on (https://en.wikipedia.org/wiki/Molar_heat_capacity).
But ...
- 73
0
votes
1
answer
306
views
Why is the heat capacity of water $9R$ and not $6R$?
From the equipartition theorem, the relationship between energy and temperature in a substance is $U=\frac{NRT}{2}$ for $N$ quadratic degrees of freedom associated with a particle of that substance. ...
- 11
3
votes
3
answers
318
views
Are number of molecules per unit volume constant (say in water)?
I have a very basic doubt. I knew that
$$ \rho = \frac{m}{V} $$
And since mass is constant so volume may decrease or increase depending upon density. But suppose I have water in a beaker and I read it ...
- 265
-1
votes
3
answers
173
views
If the melting point of Oxygen is -218 Celcius and the melting point of Hydrogen is -259 Celsius, why is the melting point of water 0 Celcius?
Forgive my ignorance, but my knowledge of Physics is not much, I am not even high-school level yet.
So, out of curiosity, I thought if water is H2O, 2 Hydrogen, and 1 Oxygen, then why is water's ...
- 109
0
votes
1
answer
977
views
Is there a way to calculate the number of degrees of freedom of water?
Say we have liquid water. We are given specific heat of water $C=4.2kJ(kg*K)$, a number of molecules in a mol $N_A=6*10^{23}$. The atomic weight of water is $18g/mol$, and the Boltzmann's constant is $...
19
votes
5
answers
3k
views
Are water molecules at the surface closer or farther apart than the molecules inside?
My lecturer says that since the energy of the molecules on the surface is higher (less negative), then at equilibrium there will be less molecules on the surface, hence the molecules on the surface ...
- 449
0
votes
1
answer
66
views
Why is the Ocean Blue? [closed]
I'm writing an article on the physical property that binds Music and Water -- Harmonics. I understand that the blueness of ocean water is due to the three vibrational modes of water (i.e, symmetric, ...
- 165
-4
votes
1
answer
184
views
Who first modelled water as a tetrahedron?
Who first modelled water as a tetrahedron? In this model the oxygen is at the center and the two hydrogens are at the vertices (I think, or maybe somewhere along the edges?).
Source
This gives the ...
- 1,297
1
vote
1
answer
129
views
Water molecule $\text{H-O-H}$ angle in electrostatic field
An image showing water molecule within a cylinder with positive charge on the inside and negative on the outside. To what extent will the $\text{H-O-H}$ angle adjust itself to the electrostatic force? ...
- 19
36
votes
2
answers
7k
views
Why isn't the molecule of water linear straight?
When you see models of water you see something like this:
The hydrogens in the water molecule become negatively charged because the oxygen pulls electrons more. So why don't they repel and move to ...
- 479