Finding Vrms given pressure, density and Temperature

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To find the root mean square velocity (Vrms) of a gas at 273K and 0.01 atm with a density of 1.24 x 10^-5 g/cm^3, the ideal gas law can be applied. The equation Vrms = sqrt(3RT/M) requires the molar mass (M), which can be derived from the gas density and the ideal gas law. The relationship between density, volume, and moles indicates that the volume does not affect the Vrms calculation if temperature and pressure remain constant. Understanding how to manipulate the ideal gas law is crucial for solving this problem. The discussion emphasizes the importance of relating density to molar mass to find the necessary variables for calculating Vrms.
sckeen1988
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Homework Statement


At 273K and .01 atm, the density of a gas is 1.24*10^-5 g/cm^3. Find the Vrms for the gas molecules.


Homework Equations



Vrms=sqrt(3RT/M) Density=m/V

The Attempt at a Solution



I tried to relate the density given to the molar mass or the number of moles somehow, but failed completely.
 
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Use the ideal gas law (assuming it is an ideal gas).
 
How can I get volume from that?
 
Hint: does the answer really depend on the volume? E.g., if you find the solution for 1 cubic meter of this gas, will you find a different solution for, say, 2 cubic meters, if all of the other given properties are the same?
 
Thanks a lot for your help.
 
pls enlighten me on how you re-solve this. I don't understand on ohw do you use ideal gas law to resolve this.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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