Solve this Kinetic theory of ideal gases (A level) question?
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Solve this Kinetic theory of ideal gases question?
Two gas containers A and B have equal volumes and contain different gases at same Temperature (T) and Pressure (P).
Show that there are equal nos. of molecules in the two containers.
**I have attempted this, is it correct?**
eq: PV=nRT
if Va = Vb and P and T are constant
then, 1 = n_a / n_b
n_a = n_b since n = N / L(avoda. no.)
Na / L = Nb / L
therefore Na = Nb **is this ok?**
The molecules in container A have mass 4 times as great as the molecules in container B. Sketch and label graphs on http://i44.tinypic.com/2u4n8u1.jpg
to show how the molecular speeds are distributed in the two containers, given that speed distribution curve for the molecules in A peaks at 200 m/s.
How does Kinetic theory account for the equal pressures at the same temperature and volume?
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Two gas containers A and B have equal volumes and contain different gases at same Temperature (T) and Pressure (P).
Show that there are equal nos. of molecules in the two containers.
You could also use the formula
PV = NKT, where K is the boltzmann's constant, and N = num of molecules
Thus, N = PV / KT
Since P, V, and T are equal for both gases, and K is a constant, thus, N is equal for both gases (shown)The molecules in container A have mass 4 times as great as the molecules in container B. Sketch and label graphs on http://i44.tinypic.com/2u4n8u1.jpg
to show how the molecular speeds are distributed in the two containers, given that speed distribution curve for the molecules in A peaks at 200 m/s.
Right where I am, tinypic is also blocked. So I shall attempt a guess at this question first.
You should know the formula for kinetic energy of a molecule. If I remember, it's 3/2 KT
So, 1/2 mv^2 = 3/2 KT
v = sqrt (3KT/m)This means, the heavier the molecule, the lower the velocity.
Hence, in general, molecules in B should travel about 2 times as fast as molecules in A.
How does Kinetic theory account for the equal pressures at the same temperature and volume?
It doesn't. PV = nRT. And n might not be the same for both. Either that or the question isn't clear.
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try copy n pasting http://i44.tinypic.com/2u4n8u1.jpg
into ur url and now try the question
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Originally posted by prg:
try copy n pasting http://i44.tinypic.com/2u4n8u1.jpg
into ur url and now try the question
Meaning of block means that copy and paste doesn't work as well when I'm in the office. -.-"
And please take note of your language. Your posts are rather 'commanding' in nature. Please note that none of us here is obliged to answer any questions. Thanks.
Basically, just draw a n-shaped curve, with the peak value of n at c = 200
For molecules in B, as calculated area, the mean speed should be twice, which is 400
So just draw a n-shaped curve with peak value of n at c = 400