Here are some general questions regarding my current reading. I am looking in my text at 2 equations for specific energy and specific enthalpy:(adsbygoogle = window.adsbygoogle || []).push({});

[itex]u = u(T,v)\qquad(1)[/itex]

[itex]h = h(T,p)\qquad(2)[/itex]

Question 1: Are not the properties fixed byany2 independent priorities? Why have we chosen to speak of u as u(T, v) in lieu of u(T, p) and the same for h ? Is it more convenient to out them in these terms for some reason?

Now, if we put (1) and (2) in differential form, we have:

[tex]du = \left(\frac{\partial{u}}{\partial{T}}\right)_v dT + \left(\frac{\partial{u}}{\partial{v}}\right)_T dv\qquad(3)[/tex]

[tex]dh = \left(\frac{\partial{h}}{\partial{T}}\right)_p dT + \left(\frac{\partial{h}}{\partial{p}}\right)_T dp\qquad(4)[/tex]

Question 2:

It says that for an ideal gas:

[tex]\left(\frac{\partial{u}}{\partial{v}}\right)_T \text{ and }\left(\frac{\partial{h}}{\partial{p}}\right)_T [/tex]

areequal to zero. Can someone clarify this? Is there some mathematical reasoning behind this? Or is this simply something that we have observed? Or both?

Question 3:

Going along with assumptions above (i.e., dh/dp = 0 and du/dv = 0) we can assert that for an ideal gas, specific energy and specific enthalpy are both functions of temperature alone, correct?

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# Thermodynamic properties of ideal gases

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