What is the average speed of gas molecules in a given volume and pressure?

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AI Thread Summary
The discussion revolves around calculating the average speed of helium gas molecules given specific parameters, including the mass of a helium atom, the number of moles, volume, and pressure. The user has already determined the temperature of the gas but seeks clarification on whether to use the mass of a single helium atom as the molar mass in the equation for root mean square speed (Vrms). It is emphasized that the mass of a single atom should not be used directly as molar mass in this context. The conversation highlights the importance of correctly applying the ideal gas equations and understanding the relationship between mass, moles, and molecular speed. The thread concludes with a focus on ensuring accurate calculations for gas properties.
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Homework Statement


The mass of a single HE atom is 6.65e-27kg. You have 5.00e-6 mole of HE gas which is occupying a volume of 1.00e-4m^3. when at pressure of 100Pa. Determine the temp of gas AND the average speed of the gas molecules.

**I've found the temp of gas i need help on the avg speed - i believe I'm close

Homework Equations


Vrms=\sqrt{3(R)(T)/(M)}


The Attempt at a Solution


Vrms=\sqrt{3(8.31J/mol K)(241)/(6.65e-27kg?)}

i'm not certain if i use 6.65e-27kg as molar mass?
 
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hatcheezy said:

Homework Statement


The mass of a single HE atom is 6.65e-27kg.
Note it gives you the mass of a single atom

hatcheezy said:
You have 5.00e-6 mole of HE gas
This is the amount of moles present

hatcheezy said:
i'm not certain if i use 6.65e-27kg as molar mass?
After reading the above do you still think this?
 
ahh i do apologise i had not realized you have calculated the temperature, please ignore the post above
 

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