The right-hand side of this equation is called the Poynting factor after the British physicist who derived it at the turn of the 20th century.

Example: What is the vapor pressure of water at 500 atm if the reference state is the normal boiling point?

This choice of reference state implies T = 373 K and psat,ref = 1 atm. The molar volume of water at this state (from steam table A.1) is vL = 1.88x10-5 m3/mole. With these values, and converting the pressure difference to 5x107 Pa, Eq (5.17) gives a Poynting factor of 1.35, or pSat = 1.35 atm.

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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