- #36
voko
- 6,054
- 391
rogerk8 said:Is it correct to say that below this critical temperature gases may be converted into liquid?
It is only below the critical temperature that they can. Check out "supercritical fluid".
rogerk8 said:Is it correct to say that below this critical temperature gases may be converted into liquid?
The average translational kinetic energy is NkT/2 for each translational degree of freedom, so <KE> = 3NkT/2rogerk8 said:Jesus, I know nothing but please consider this:
[tex]U=KE+PE[/tex]
and
[tex]KE=kT≈\frac{mv^2}{2}[/tex]
and
[tex]\frac{PV}{N}=kT[/tex]
Then
[tex]U=kT+kT[/tex]
?
Do you have a specific question about PE and pressure?rogerk8 said:Thank you once again Andrew Mason!
I am thankful for all your help!
Now I know that there is a kinetic energy of NkT/2 per degree of freedom and that this is associated with potential energy as well.
My brand new understanding of internal energy is thus
[tex]U=KE+PE=fNkT/2[/tex]
But what about PE and pressure?
Roger
Andrew Mason said:Do you have a specific question about PE and pressure?
First of all you have to have a non-ideal gas with attractive forces between molecules. For such a gas PE increases with volume (as the space between molecules grows, on average, so does PE). If T remains constant (i.e. KE is constant) what happens to the pressure? (hint: how is pressure related to the rate at which molecules change momentum in striking the container walls? If KE is constant, but the distance between walls increases, what happens to the frequency of molecules colliding with the wall?).
AM