Kinetic theory

The kinetic theory of gases is a theory that explains the macroscopic properties of gases by consideration of their composition at a molecular level.

Rms speeds of molecules etc.

From the kinetic energy formula we find:

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:v_{rms}^2 = 24,940 T / molecular mass

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with v in m/s and T in kelvins.

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For standard temperature the root mean square speeds are:

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• thermal neutrons 2610 m/s
• hydrogen 1846 m/s
• nitrogen 493 m/s
• oxygen 461 m/s

The most probable speeds are 81.6% of these (e.g. for thermal neutrons 2131 m/s), and the mean speeds 92.1%, see also distribution of speeds.

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