What is the relationship between entropy and pressure in thermodynamics?

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The discussion focuses on deriving the relationship between entropy (S) and pressure (P) in thermodynamics, specifically seeking the expression for the partial derivative of enthalpy (H) with respect to pressure at constant temperature. The user starts with the differential form of entropy and applies various thermodynamic relationships, including the Maxwell relations and the exact differential of Gibbs free energy. They express the challenge of incorporating variables such as pressure, volume, temperature, and specific heat capacities into their equations. Ultimately, the user finds progress by utilizing the relationship between temperature and entropy in the context of enthalpy and pressure. The conversation highlights the complexity of thermodynamic relationships and the mathematical intricacies involved in deriving them.
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Homework Statement
Derive ##(\frac{\partial H}{\partial P})_t## in term of ##P,V,T, \beta, \kappa, c_p##
Let H = H(T,P)
Relevant Equations
##ds = (\frac{\partial S}{\partial H})_p dH + (\frac{\partial S}{ \partial P})_H dP##

##dH = (\frac{\partial H}{\partial T})_p dT + (\frac{\partial H}{ \partial P})_T dP##
Hi,
Starting from dS in term of H and P, I'm trying to find ##(\frac{\partial H}{\partial P})_t## in term of ##P,V,T, \beta, \kappa, c_p##.
Here what I did so far.

##ds = (\frac{\partial S}{\partial H})_p dH + (\frac{\partial S}{ \partial P})_H dP##

##ds = (\frac{\partial S}{\partial H})_p [ (\frac{\partial H}{\partial T})_p dT + (\frac{\partial H}{ \partial P})_T dP] + (\frac{\partial S}{ \partial P})_H dP##

##\frac{\partial S}{\partial P} = (\frac{\partial S}{\partial H})_p (\frac{\partial H}{\partial T}) (\frac{\partial T}{\partial P}) + (\frac{\partial H}{\partial P})_T (\frac{\partial S}{\partial H})_P + (\frac{\partial S}{\partial P})_H##

##(\frac{\partial S^2}{\partial T \partial P}) = (\frac{\partial S}{\partial H})_p (\frac{\partial H}{\partial T}) (\frac{\partial T}{\partial P}) + (\frac{\partial H}{\partial P})_T (\frac{\partial S}{\partial H})_P + \frac{d}{dP}(\frac{\partial S}{\partial P})_H##

##(\frac{\partial H}{\partial P})_T = -(\frac{\partial H}{\partial S})_P (\frac{\partial S}{\partial H})_P (\frac{\partial H}{\partial T})(\frac{\partial T}{\partial P})##

From there, I'm stuck. I don't see how I can get ##P,V,T, \beta, \kappa, c_p##

Thank you
 
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Start with the exact differential dG=-SdT+VdP, which means that $$\left(\frac{\partial S}{\partial P}\right)_T=-\left(\frac{\partial V}{\partial T}\right)_P$$
 
I have to start with ds in term of dh and dp.
I just saw in the original post, those P should be in index.

I finally found something using ##Tds = dh - vdp##
 
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