Kinetic Theory and Thermophysical Properties

AI Thread Summary
The discussion centers on deriving the viscosity and mass diffusivity of an ideal gas using kinetic theory. It highlights that viscosity, distinct from liquid viscosity, can be derived from kinetic principles, with Maxwell being a key figure in this derivation. The conversation also touches on the concept of mass diffusivity, questioning whether it applies to individual gases or only to mixtures. References to foundational texts, such as Hirschfelder, Curtiss, and Bird's work, are provided for further theoretical insights. Overall, the thread emphasizes the importance of understanding these properties through kinetic theory.
Clausius2
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Is there any way to derive the viscosity \mu of an ideal gas from kinetic theory?

Also: Is there any way to derive the mass diffusitivity D of an ideal gas from kinetic theory?.

Another one: does it make sense to talk about the mass diffusivity of an individual gas (for instance D_i), or such magnitude is always referred to a gaseous mixture (i.e D_{ij})?.

Some web link of bibliography would be greatly appreciated.
 
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Clausius2 said:
Is there any way to derive the viscosity \mu of an ideal gas from kinetic theory?

Some web link of bibliography would be greatly appreciated.
Apparently there is. Viscosity of a gas is interesting. It is entirely different than viscosity of liquids. Seems Maxwell was the first to derive it from kinetic theory. See: http://www.math.umd.edu/~lvrmr/History/Foundations.html

"In a gas, viscous force originates not in the forces between neighboring molecules but in the transfer of momentum that occurs when a molecule from a faster-moving stream wanders over to a slower-moving stream and collides with a molecule there. The rate of momentum transfer increases with the average molecular speed, so (1) the viscosity increases with temperature."

AM
 
See Hirschfelder, Curtiss, and Bird, Molecular Theory of Gases and Liquids for the theoretical treatments --- it'll be in the library.
 
Andrew Mason said:
Apparently there is. Viscosity of a gas is interesting. It is entirely different than viscosity of liquids. Seems Maxwell was the first to derive it from kinetic theory. See: http://www.math.umd.edu/~lvrmr/History/Foundations.html

"In a gas, viscous force originates not in the forces between neighboring molecules but in the transfer of momentum that occurs when a molecule from a faster-moving stream wanders over to a slower-moving stream and collides with a molecule there. The rate of momentum transfer increases with the average molecular speed, so (1) the viscosity increases with temperature."

AM

Thanks both of you.

AM, I am looking for a formulation, not only the historical background of the stuff.
 
Bystander said:
See Hirschfelder, Curtiss, and Bird, Molecular Theory of Gases and Liquids for the theoretical treatments --- it'll be in the library.

Thank you very much Bystander. I have found what I was looking for in Hirschfelder's book.
 
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