What Affects the RMS Speed Difference Between Helium Atoms and Molecules?

AI Thread Summary
The discussion focuses on calculating the new pressure of helium after its root mean square (rms) speed increases by 50% due to added heat. It highlights the relevant equation for rms speed, which is dependent on temperature and mass. A key point of confusion arises regarding whether the rms speed of helium atoms differs from that of helium molecules, with clarification that helium is a monatomic gas, thus the rms speed for both is the same. The mass of a helium atom is noted as 6.6x10^-26 kg, which is essential for calculations. Understanding these concepts is crucial for solving the homework problem effectively.
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Homework Statement


Heat is added until the rms speed of a helium atom has increased 50%. Find new pressure. (Not all parameters given.)


Homework Equations


rms = (3kT/m)1/2
mass of molecule = mass of mole/NA
Then, mass of helium molecule is 6.6x10-26kg

The Attempt at a Solution


Question: Is rms speed of a helium molecule the same as the rms speed of an atom. Yes, because the atoms make up the molecule? No, helium is diatomic (right?) and so that has to be taken into account??
 
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