Problem: The average kinetic energy of the molecules in a gas sample depends only on the temperature, T. But given the same kinetic energies, a lighter molecule will move faster than a heavier molecule. rms speed = √3RT/M  where R=8.314 J/(mol • K) and M is molar mass in kilograms per mole. Note that a joule is the same as a kg • m2/s2. What is the rms speed of N2 molecules at 287 K?What is the rms speed of He atoms at 287 K?

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FREE Expert Solution
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Problem Details

The average kinetic energy of the molecules in a gas sample depends only on the temperature, T. But given the same kinetic energies, a lighter molecule will move faster than a heavier molecule. 

rms speed = √3RT/M  where R=8.314 J/(mol • K) and M is molar mass in kilograms per mole. Note that a joule is the same as a kg • m2/s2

What is the rms speed of N2 molecules at 287 K?




What is the rms speed of He atoms at 287 K?


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