How Many Neon Molecules Have Velocities Between 100 and 200 m/s?

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SUMMARY

The discussion focuses on calculating the number of neon molecules with velocities between 100 and 200 m/s in a sealed bottle containing 1 mole of neon and 1 mole of argon at 295 K. The solution utilizes the Maxwell-Boltzmann velocity distribution and involves integrating the distribution function. The user initially encounters issues with the y-axis units and the calculated number of particles, which was approximately 4E20, but later resolves the problem independently.

PREREQUISITES
  • Understanding of Maxwell-Boltzmann distribution
  • Familiarity with Boltzmann distribution equations
  • Knowledge of integration techniques in calculus
  • Proficiency in using symbolic computation tools like MATLAB
NEXT STEPS
  • Study the derivation of the Maxwell-Boltzmann distribution
  • Learn about the application of the Boltzmann distribution in statistical mechanics
  • Explore numerical integration methods in MATLAB
  • Investigate the significance of temperature and molecular mass in gas behavior
USEFUL FOR

Students in physics or chemistry courses, particularly those studying thermodynamics and statistical mechanics, as well as educators and tutors assisting with gas velocity calculations.

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Homework Statement


A sealed bottle at 1 atm of pressure holds 1 mole of neon and 1 mole of argon gas at a temperature of 295 K.

Find the number of molecules of neon which have velocities between 100 and 200 (m/s).


Homework Equations



Boltzmann distribution

The Attempt at a Solution



"%Maxwell-Boltzmann velocity distribution
syms v
m= 0.0201797;
T=295;
R=8.31
btm=2*pi*R*T;
exponet=((-m*v^2)/(2*R*T))
F=[(4*pi*((m/btm)^1.5))*v^2*exp(exponet)]*1E24
ezplot(F,[0 1500])
integral_all=vpa(int(F, v, 0, inf))
%integral_all = 1 so it checks out
integral_range=vpa(int(F, v, 100, 200))


so I plotted the speed distribution and integrated it from 0
to infinity and it equals 1, so I think I'm on the right
track. However you'll notice the y-axis units don't really
make sense. Even when I fudge it by E24 it's still doesn't
come out right. (I know what you're thinking about a 24
order of magnitude fudge) I get about 4E20 particles which
apparently isn't the right answer. After all this, I'm not
sure if I can bring myself to count up the little hash marks
on the screen to get the area, at least not tonight anyway. "

I copied this from my class's forum btw. i didnt write this but i did exactly the same thing (and no i didnt copy him, its just the obvious choice). can someoene help us tellin us what in gods name we are doing wrong?
 
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nvm i solved it
 

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