Macro/ micro connections- pressure

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SUMMARY

The discussion focuses on estimating the number of nitrogen gas molecules within a 1.3m³ cube at 20°C and 1.5 atm pressure, specifically those with speeds between 700 m/s and 1000 m/s. The initial calculation used the equation N = 3PV/(mv²rms), resulting in an incorrect estimate of 0.024 molecules. Participants concluded that applying the Maxwell-Boltzmann distribution is necessary for accurate results, as it accounts for the distribution of molecular speeds in a gas.

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Homework Statement


A 1.3m×1.3m×1.3m cube of nitrogen gas is at 20∘C and 1.5 atm. Estimate the number of molecules in the cube with a speed between 700 m/s and 1000 m/s.

Homework Equations


P= (1/3) (N/V) (Mv2rms)

The Attempt at a Solution


20oc = 293 K
1.5 atm = 151950 Pa

Solving for N
N= 3PV/(mv2rms)

N= 3(151950)(2.197) / (28 x 12202)
N= 0.024 Molecules ?
This doesn't seem right?
 
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It looks like you need to use the Maxwell- Boltzmann distribution for this.
 

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