Thermodynamics: Internal Energy and Enthelpy

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The discussion centers on the relationship between enthalpy (H), internal energy (U), pressure (p), volume (V), and temperature (T) in the context of ideal gases. It clarifies that enthalpy can be expressed as H = U + pV and also as H = U + nRT, where n is the number of moles and R is the ideal gas constant. The transition from U + nRT to H(T) is explained through the properties of a monoatomic ideal gas, where U is defined as (3/2)PV, leading to H being expressed as (5/2)PV or (5/2)nRT. This indicates that enthalpy is a function of temperature alone, although it also depends on the number of moles, which can be normalized by defining h = H/n, making h an intensive quantity. The discussion concludes with an acknowledgment that this explanation clarifies the relationship.
leah3000
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H = U+ pV
pV = nRT

H= U+ nRT

H= H (T)

I don't understand the transition from U+ nRT to H (T)

Can someone explain this?

I get that H = U + pV

But how is H= U+ nR
 
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For a monoatomic ideal gas, U=(3/2) PV. Hence, H=(5/2) PV=(5/2) nRT
Which shows that H for an ideal gas is a function of T alone ,i.e, H=H(T).
Of course it is also function of n since it is extensive quantity. However, this dependence is easy to get rid of by defining h=H/n which is an intensive quantity.
 
thank you...that clears it up!
 

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