Calculating Average Kinetic Energy and RMS Speed of Gas Molecules

AI Thread Summary
To calculate the average kinetic energy and RMS speed of gas molecules in a mixture of helium and argon at 150 degrees Celsius, the Boltzmann constant (1.38 x 10^-23) is used in the formula 1/2mv^2 = 3/2kT. It's crucial to convert the temperature to Kelvin for accurate results. The discussion highlights a common mistake of neglecting this conversion. Once the temperature is correctly converted, the calculations for kinetic energy and RMS speed can be completed. Properly applying these principles will yield the desired values for both gases.
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hi all

if you have a cylinder with helium and argon in it, and the mixture is at equilibrium, with a temperature of 150 degrees celsius. what is the average kinetic energy of each gas molecule?, and what is the rms speed of each type of molecule?

im aware of the theory behind this, but it seems that i just cannot obtain the answer.
im using the formula
1/2mv^2 (kinetic energy) = 3/2kT
i think I am going wrong with calculating k, isn't that a constant, 1.38 X 10 ^ -23.

thanx for any help
 
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Yes that k is the Boltzmann constant, with that value. Perhaps you are forgetting to convert to kelvin?
 
hmm, yes, i did forget to convert to kelvin, i thought i did, oh well, thanks for the notice!
 

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