Calculating Air Kinetic Energy & Vrms of N2 & O2

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At a temperature of 293K, the average kinetic energy of air, primarily composed of N2 and O2, is calculated to be 6.1E-21 J. The root mean square velocity (Vrms) for N2 is approximately 511 m/s, while for O2 it is about 478 m/s. These calculations assume ideal gas behavior for both gases. The results provide insights into the molecular dynamics of air at room temperature. Understanding these values is essential for analyzing gas behavior and interactions.
cowgiljl
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The question is Air is primarly a mixture of N2 and O2. Assume that each gas behaves as an ideal gas. If the temperture is is 293K calculate the kinetic energy of the air and calculate the Vrms of N2and O2
what I know is Kb = 1.38E-23 J/K
mass of one molecule of N2 is 4.65E-26
mass of one molecule of O2 is 5.31E-26

formula used KE= 3/2*Kb*T
Ke = 6.1E-21 J

for the Vrms of N2 & O2
Vrms = square root of 3*Kb*T/Mass of N2 O2

Vrms of N2 = 510.74 m/s
Vrms of O2 = 477.95 m/s

is this correct?
 
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All correct; just trim those "sig figs" to 511 and 478 m/s.
 


Yes, your calculations for the kinetic energy and Vrms of N2 and O2 at 293K are correct. This means that at room temperature, the average kinetic energy of air molecules is 6.1E-21 J and the average velocity of N2 and O2 molecules is 510.74 m/s and 477.95 m/s, respectively. This information can be useful in understanding the behavior of gases and their interactions with their surroundings.
 
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