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## Main Question or Discussion Point

Does anyone have coefficients of thermal expansion in F^-1 instead of in C^-1. I have worked out an equation from thermodynamic first principals that derives the throttling equation I then did the first order non-seperable differential equation:

dT/dP = C1*T - C2

to get the following equation:

P2 = {[ln(T1/(T2-(C2/C1)))]/-C1} + P1

Where C1 = V*B/Cp*m and C2 = V/Cp*m

but this equation only gives appropriate solutions for P2 if B is ~0.02 F^-1 or in this range, the tabulated valves for methanol are 0.00135 F^-1 which gives me imaginary numbers when I take the natural log using this B value.

This has been extremely frustrating because I feel like I am very close to solving this blocked in thermal expansion problem to get a pressure but the tabulated values I find are not working with my equation, I am wondering if its because the few websites that state this value are in C^-1 and I am just multiplying by 9/5 to get B = .00135 F^-1.

dT/dP = C1*T - C2

to get the following equation:

P2 = {[ln(T1/(T2-(C2/C1)))]/-C1} + P1

Where C1 = V*B/Cp*m and C2 = V/Cp*m

but this equation only gives appropriate solutions for P2 if B is ~0.02 F^-1 or in this range, the tabulated valves for methanol are 0.00135 F^-1 which gives me imaginary numbers when I take the natural log using this B value.

This has been extremely frustrating because I feel like I am very close to solving this blocked in thermal expansion problem to get a pressure but the tabulated values I find are not working with my equation, I am wondering if its because the few websites that state this value are in C^-1 and I am just multiplying by 9/5 to get B = .00135 F^-1.