Real gases, Kaplan inconsistency

[Ahhdumb]

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So in the beggining of the gas section for Kaplan they say that at high pressure the size of the particle becomes relatively large to the distance between them so they take up more volume than predicted by gas law.
However later in the paragraph they sum everything up by saying "generally at high pressure and at low temp the actual vol of the gas is less than predicted by the ideal gas law"

Any clarification would be great.

 

[AliDeLaLouisa]

Real gases deviate from ideal behavior when thier molecules are close together. High pressure pushes gas molecules together causing deviations from the ideal behavior. Lower temperatures can cause gas molecules to settle close together also resulting in deviations from ideal behavior.

Think Volume: V real is greater than V ideal

Think Pressure: P real is less than P ideal



Ideal:
-volume is negligible
-elastic
-at STP volume = 22.4L
-no intermolecular attractions present

Real:
- at STP volume is lower than 22.4L, therefore low pressure and high temperature will make the real gas act more like an ideal gas...
-inelastic collisions
- intermolecular attractions present
-volume is present

Hope this helps🙂 Most question in my review focus on ideal gas but its important to know real gas as it relates to van der waals focusing on the deviations from ideal gas.

 

[Phantastic]

So in the beggining of the gas section for Kaplan they say that at high pressure the size of the particle becomes relatively large to the distance between them so they take up more volume than predicted by gas law.
However later in the paragraph they sum everything up by saying "generally at high pressure and at low temp the actual vol of the gas is less than predicted by the ideal gas law"

Any clarification would be great.

I don't think it contradicts itself:

At high pressures, the size of the molecule is not negligible in comparison to the size of the gas. They do take up more volume which means your gas occupies less volume. I think this is how I've come to terms with it but I'm probably incorrect in some way...just have that feeling.