Deriving (∂T/∂P)s from T, V, Cp, α, and κT

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mdawg467
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Im trying to understand this concept of deriving an expression for ([itex]\frac{\partial T}{\partial P}[/itex])s in terms of T, V, Cp, [itex]\alpha[/itex], and [itex]\kappa[/itex]T

([itex]\frac{\partial T}{\partial P}[/itex])s is evaluated by measuring the temperature change and the specific volume change accompanying a small pressure change in a reversible adiabatic process.

I attached the derivation that the book does, but I cannot follow it. Any help would be greatly appreciated!

Thanks
 
Attachments
  • Chain of partial derivative equalities using Jacobians, starting with (dT/dP) at constant S, ending with V alpha T over Cp, with underlined S and P subscripts.
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There are a lot of steps in that simple looking derivation. Where are you lost?
 
Don't understand the notation in your thumbnail, but append my derivation, expressed in ordinary partial derivative notation.
 
Attachments
  • Handwritten derivation of (∂T/∂P)s: states Cp = T(∂S/∂T)p, a Maxwell relation (∂T/∂P)s = (∂V/∂S)p, chain rule to (∂V/∂T)p(∂T/∂S)p, then TV{(1/V)(∂V/∂T)p}/{T(∂S/∂T)p} = TV(α/Cp), with α = V(∂V/∂T)p and Cp = T(∂S/∂T)p noted.
    Thermod formula.jpg
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Philip Wood said:
Don't understand the notation in your thumbnail, but append my derivation, expressed in ordinary partial derivative notation.

Thanks dude, I was getting lost with the notation as well. This helps out big time.. Not sure what the book was doing lol.