## approximate ideal gas law

$PV=nRT$

Katherine Wu 1H
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### approximate ideal gas law

Identify reactions where the ideal gas law can be used as an approximation.
I'm a bit confused as to what this is referring to?

LBacker_2E
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### Re: approximate ideal gas law

I think this is necessary when you are trying to find the equilibrium constant K. For example, if you are trying to solve for Kc and you are given the partial pressure, you can then plug that into PV=nRT to solve for n/V which is the molarity or concentration. Once you have the problem in terms of concentration, you can solve it like a normal equilibrium problem.

805303639
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### Re: approximate ideal gas law

The ideal gas law is a limiting law that performs well as P approaches 0. High pressures highlight its shortcomings. Van der Waals equation, another approximation of gas behavior, is more accurate because it accounts for the volume of the gas molecules and their intermolecular attractions. However, it is an unwieldy expression and PV=nRT suffices in most situations.

Kassidy Ford 1I
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### Re: approximate ideal gas law

The ideal gas law assumes that the gases are their ideal state when it is used. This might not be true, but especially for this course we always assume that the gases are at their ideal state so that we can use the equation.