Fundamental equation and state equations of the ideal gas

In summary, the conversation discusses finding the fundamental equation of a monoatomic ideal gas in the Helmholtz potential, enthalpy, and Gibbs function representations. The equation is given as S= \frac{NS_0}{N_0} +NR \ln \left [ \left ( \frac {U}{U_0} \right ) ^{3/2} \left ( \frac{V}{V_0} \right ) \left ( \frac {N}{N_0} \right ) ^{-5/2} \right ] and the task is to find the equations of state by differentiation. The attempt at a solution involves using the given fundamental equation to obtain F(T,V,N)=
  • #1
fluidistic
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Homework Statement


Find the fundamental equation of a monoatomic ideal gas in the Helmholtz potential representation, in the enthalpy representation, and in the Gibbs function representation. Assume the fundamental equation [itex]S= \frac{NS_0}{N_0} +NR \ln \left [ \left ( \frac {U}{U_0} \right ) ^{3/2} \left ( \frac{V}{V_0} \right ) \left ( \frac {N}{N_0} \right ) ^{-5/2} \right ][/itex]. In each case find the equations of state by differentiation of the fundamental equation.


Homework Equations


Helmholtz: F=U-TS. But F(T,V,N)
PV=NRT.
[itex]U=\frac{3NRT}{2}[/itex].


The Attempt at a Solution


I first deal with Helmholtz.
If I understand well, I must get F(T,V,N)=U-TS. I already have U in terms of T and N. The last task is therefore to get S in terms of T,V and N which seems easily made by using the given fundamental equation.
It gives me [itex]F(T,V,N)=\frac {3NRT}{2}-T \{ NK_1 +NR \ln \left [ \left ( \frac{V}{V_0} \right ) \left ( NTK_2 \right ) ^{3/2} \left ( \frac{N}{N_0} \right ) ^{-5/2} \right ] \}[/itex].
So far I wonder if my approach is a right one. Is it ok so far?
 
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  • #2
I just got a reminder that this question went unanswered.
Tbh, I have no clue. Well... maybe if I think hard about it...
Erm... @fluidistic, can you perhaps write an answer by now?
 

What is the fundamental equation of an ideal gas?

The fundamental equation of an ideal gas is PV = nRT, where P is the pressure of the gas, V is the volume, n is the number of moles of gas, R is the ideal gas constant, and T is the temperature in Kelvin.

What is the state equation of an ideal gas?

The state equation of an ideal gas is the ideal gas law, which states that the product of pressure and volume is directly proportional to the number of moles and temperature. In equation form, it is written as PV = nRT.

How is the ideal gas law derived from the fundamental equation?

The ideal gas law, PV = nRT, is derived from the fundamental equation by assuming that the gas is ideal, meaning that it follows certain assumptions such as having no intermolecular forces and occupying negligible volume. By applying these assumptions, the fundamental equation simplifies into the ideal gas law.

What are the units of the ideal gas constant, R?

The units of the ideal gas constant, R, depend on the units used for pressure, volume, number of moles, and temperature. However, the most commonly used units are atmospheres (atm) for pressure, liters (L) for volume, moles (mol) for number of moles, and Kelvin (K) for temperature. In this case, the units of R would be L*atm/mol*K.

Can the ideal gas law be used for real gases?

The ideal gas law can be used for real gases under certain conditions, such as at low pressures and high temperatures. However, as the pressure increases and the temperature decreases, the behavior of real gases deviates from that predicted by the ideal gas law. In these cases, more accurate equations, such as the van der Waals equation, should be used.

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