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why doesn't volume affect the boltzmann curve

why doesn't volume affect the boltzmann curve
Original post by esmeralda123
why doesn't volume affect the boltzmann curve


If you look at the axis typically used, i.e. Proportion of molecules with Energy (E) and Energy (E). Volume wouldn't affect it. There would be more successful collisions per unit of time, but the velocity wouldn't change. Boltzmann distribution shows the number of molecules at a certain energy and hence velocity. Volume wouldn't affect velocity
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Original post by Kyber Ninja
If you look at the axis typically used, i.e. Proportion of molecules with Energy (E) and Energy (E). Volume wouldn't affect it. There would be more successful collisions per unit of time, but the velocity wouldn't change. Boltzmann distribution shows the number of molecules at a certain energy and hence velocity. Volume wouldn't affect velocity


what do you mean by velocity?
Original post by esmeralda123
what do you mean by velocity?


Energy = Kinetic Energy

Kinect energy is proportional to velocity for these small molecules
Original post by esmeralda123
why doesn't volume affect the boltzmann curve


The key is that the average kinetic energy of a particle is directly proportional to the absolute temperature AND that the statistical distribution of energy is given by the Maxwell Boltzmann equation.

Increasing number of particles cannot affect either of the above.
Original post by charco
The key is that the average kinetic energy of a particle is directly proportional to the absolute temperature AND that the statistical distribution of energy is given by the Maxwell Boltzmann equation.

Increasing number of particles cannot affect either of the above.


Just a query, if the pressure is vastly increased, won't there be more friction, hence a higher temperature? Hence a higher average kinetic energy? Or is this a cancelling out effect since other particles are being sped up and others slowed down by this?
Original post by Kyber Ninja
Just a query, if the pressure is vastly increased, won't there be more friction, hence a higher temperature? Hence a higher average kinetic energy? Or is this a cancelling out effect since other particles are being sped up and others slowed down by this?


According to the ideal gas law, PV = nRT, there are only 3 ways to increase the pressure.

1. Decrease the volume.
2. Increase the number of moles of gas
3. Increase the temperature


1. Has no effect on T, as PV = constant
2. Has no effect on T, as n is proportional to P
3. Has an effect on T, obviously

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