Which should I use to prove this?

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(∂s/∂P) at constant volume =1/T ×(∂u/∂T)at constant volume × (∂T/∂P) at constant volume

s(P,v)
Tds= du +pdv
h= u + pv
h(P,v)
u(P,v)
or other formula?
How am I going to choose ? Please guide

Thank
 
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Outrageous said:
(∂s/∂P) at constant volume =1/T ×(∂u/∂T)at constant volume × (∂T/∂P) at constant volume

s(P,v)
Tds= du +pdv
h= u + pv
h(P,v)
u(P,v)
or other formula?
I'm not expert on gas theory, so I'll just treat this as an algebraic question.
Of those 'formulae', only two are equations. One of those two involves h, not mentioned anywhere else. So that leaves Tds= du +pdv as the only candidate.
What would the constant volume version of that equation look like?
 
haruspex said:
I'm not expert on gas theory, so I'll just treat this as an algebraic question.
Of those 'formulae', only two are equations. One of those two involves h, not mentioned anywhere else. So that leaves Tds= du +pdv as the only candidate.
What would the constant volume version of that equation look like?

The others also can become equation like s is function of v and p
So ∂s=(∂s/∂p)dp + (∂s/∂v)dv
Then h=u + pv , can be dh= du + Pdv + vdp
This is all just dealing with mathematics , please teach me how to choose
Do you mean why did I put constant volume there? It means by keeping volume constant then only differentiate.
Thank
 
Outrageous said:
(∂s/∂P) at constant volume =1/T ×(∂u/∂T)at constant volume × (∂T/∂P) at constant volume

s(P,v)
Tds= du +pdv
h= u + pv
h(P,v)
u(P,v)
or other formula?
How am I going to choose ? Please guide

Thank

Have you considered using the Maxwell relations?

BiP
 
Bipolarity said:
Have you considered using the Maxwell relations?

BiP

haruspex said:
No, I mean take this equation: Tds= du +pdv
and turn it into an equation involving partial derivatives, v being constant.

I am not really understand what is Maxwell ,
I only can get (∂s/∂P) at constant volume = (1/T)(∂h/∂P)constant volume -(v/T)
 
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This first , only that second deriavative
 

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