Thermodynamics: Show that the two relations give Pv = RT

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SUMMARY

The discussion focuses on deriving the ideal gas law, Pv = RT, using two key thermodynamic relations for an ideal gas. The first relation, (∂P/∂v) at constant T = -P/v, describes the slope of an isotherm, while the second, (∂P/∂T) at constant v = P/T, describes the slope of an isochore. The user attempts to manipulate these equations through partial derivatives and differential equations but struggles with the integration process. The solution involves recognizing the relationships between the variables and correctly applying integration techniques to arrive at the ideal gas law.

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  • Understanding of partial derivatives in thermodynamics
  • Familiarity with the ideal gas law Pv = RT
  • Basic knowledge of differential equations
  • Concept of isotherms and isochores in thermodynamic processes
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  • Study the application of partial derivatives in thermodynamics
  • Learn about the derivation of the ideal gas law from first principles
  • Explore integration techniques for solving differential equations
  • Investigate the physical significance of isotherms and isochores
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Homework Statement



For an ideal gas the slope of an isotherm is given by

(∂P/∂v) constant T = -P/v

and that of an isochore is

(∂P/∂T) constant v = P/T

Show that these relations give Pv = RT

Homework Equations



Pv = RT

The Attempt at a Solution



I have never worked with partial derivatives before encountering this problem so I am unfamiliar with the rules and operations involved. I tried setting them equal, adding them to each other but I just don't know where I am going.
 
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You can treat each of the equations as an ordinary differential equation where the independent variable is V and T respectively. When you solve them, you will have two constants. But these constants must be then functions of the "constant" variable, T and V respectively. Then you should be able to find those functions and get the ideal gas law.
 
Ok so I got up to this step.

dP = -P/v dv + P/T dt

Im unsure of how to proceed from here
 
Divide by P and then integrate.
 
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