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

[marmot]

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

boltzman 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?

 

[marmot]

nvm i solved it