Zv V

Absent pV work and heat exchange with the surroundings, the First law requires that the internal energy of the mixture be equal to the sum of the values of the pure components, or:

where u is the molar internal energy of component i and u is the internal energy per mole of mixture or solution. Because mixing occurs at constant pressure and there is no change in system volume, a similar equation applies to the enthalpy:

Since the specific heats CV and CP are temperature derivatives of u and h, respectively, the same mixing rules apply:

where CVi and CPi are the molar specific heats of pure component i.

The entropy of an ideal mixture or solution is not as transparent as are U and H. This issue is treated in Sect. 7.2.2

Getting Started With Solar

Getting Started With Solar

Do we really want the one thing that gives us its resources unconditionally to suffer even more than it is suffering now? Nature, is a part of our being from the earliest human days. We respect Nature and it gives us its bounty, but in the recent past greedy money hungry corporations have made us all so destructive, so wasteful.

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