Kinetic Theory of the Ideal Gas

AI Thread Summary
The discussion focuses on calculating the root mean square (rms) speed of nitrogen (N2), oxygen (O2), and carbon dioxide (CO2) molecules in air at 0.0°C and 1.00 atm using the kinetic theory of gases. The formula used is vrms = square root of (3kT/m), where k is the Boltzmann constant, T is the temperature in Kelvin, and m is the mass of the gas molecules. The user calculated the rms speed for N2 as approximately 9978.73 m/s but expressed uncertainty about the accuracy of this result. A subsequent calculation yielded a different value of 493 m/s, indicating confusion in the application of the formula. Clarification on the calculations and methodology is needed to ensure accurate results for O2 and CO2.
liz_p88
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Homework Statement



Find the rms speed in air at 0.0°C and 1.00 atm of (a) the N2 molecules (b) the O2 molecules, and (c) the CO2 molecules.

Homework Equations



vrms = square root of 3kT/m

The Attempt at a Solution



(a). 28.0u x (1.66 x 10^-27) = 4.68 x 10^-26
1.5 x (1.38 x 10-23 J/K) x 273K = 5.6511 x 10^ -21

square root of {(3)(5.6511 x 10^-21)(273)/(4.648 x 10^-26)}

9978.73 m/s

If I got this correct, I can do b and c but I honestly don't know if I did it right
 
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I did it again, this time I did

square root of (2)(5.6511 x 10^-21)/ (4.648 x 10^-26)

493 m/s
 
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