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Topic: Vandervall's equation  (Read 5288 times)

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Offline phymatter

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Vandervall's equation
« on: December 19, 2009, 01:49:29 AM »
What do the V and P in the Vandervall's equation denote???? i mean do they give Vreal and Preal or Videal and Pideal ??
i am a bit confused ,
 i know that Vreal = Videal - nb
also Preal = Pideal - an2/V2
am i wrong somewhere , all this is not fitting in well into the Vandervall's equation !
PLEASE 'HELP' !!!!!!!!!!!

Offline UG

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Re: Vandervall's equation
« Reply #1 on: December 19, 2009, 03:04:18 AM »
V= Volume P=pressure.
Just make sure you use the correct 'a' and 'b' values for a particular gas.

Offline Borek

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Re: Vandervall's equation
« Reply #2 on: December 19, 2009, 04:45:07 AM »
Real.
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Offline phymatter

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Re: Vandervall's equation
« Reply #3 on: December 19, 2009, 08:51:37 AM »
also what about the V in an2/v2 ? ::)

Offline Borek

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Re: Vandervall's equation
« Reply #4 on: December 19, 2009, 10:22:34 AM »
Real.
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Offline mbeychok

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Re: Vandervall's equation
« Reply #5 on: January 23, 2010, 03:26:45 PM »
phymatter:

First of all, I am surprised that no one has pointed out that the correct name of the equation is the van der Waal's equation.

You will find it useful to keep in mind that the van der Waal's equation is an "equation of state" and applies to real gases. Please read this article in the Citizendium online encyclopedia:

   Click here ==>  van der Waal's equation

and especially note this statement:Although the parameters "a" and "b" are referred to as "the Van der Waals constants", they are not truly constants because they vary from one gas to another; they are, however, independent of P, V and T. In other words, they are constant for the specific gas being considered.

Milton Beychok
(Visit me at www.air-dispersion.com)

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