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### Topic: Fugacity  (Read 6499 times)

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#### material

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##### Fugacity
« on: August 09, 2005, 11:00:11 AM »
Pls, I need the explanation of the physical property,called fugacity.

#### Donaldson Tan

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##### Re:Fugacity
« Reply #1 on: August 09, 2005, 11:32:51 AM »
think fugacity as a pseudo pressure.

isothermal change for a perfect gas: dg = v dp = RT (dp/p)

the Gibbs free energy of a real gas is therefore: dg = v dp = RT (df/f) where f is fugacity

notice that p is replaced with f in the real gas function.

fugacity is a measure of deviation of real gas from the ideal gas model.
« Last Edit: August 09, 2005, 11:33:53 AM by geodome »
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#### Mitch

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##### Re:Fugacity
« Reply #2 on: August 09, 2005, 03:14:19 PM »
Basically, its how much the data needs to be "fudged" in order replicate theory.
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#### ppithermo

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##### Re:Fugacity
« Reply #3 on: September 12, 2005, 05:42:55 PM »

Fugacity has the dimension of a pressure.

the ratio of the fugacity  to the pressure is the fugacity coefficient.

It gives a measure of "how much" a gas deviates from an ideal gas.

For an ideal gas, fugacity and pressure are identical