VI. The kinetic theory of gases
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物理化學(三) 應用化學系朱超原老師 1 • The velocity probability distribution • Radial distribution molecular speed • Pressure, effusion and collision • Potential energy VI. The kinetic theory of gases VI. The kinetic theory of gases
Transcript of VI. The kinetic theory of gases
Microsoft PowerPoint - PchemIII-13.ppt• Radial distribution
molecular speed • Pressure, effusion and collision • Potential
energy
VI. The kinetic theory of gasesVI. The kinetic theory of gases
() 2
vgvvf 24
Most probable speed
048 2 dv
kgm 2710660.195.39
VIVI--3. Pressure, effusion and collision 3. Pressure, effusion and collision
yvVelocity after time
y
V NAyv
v to vdv
A Area
Total pressure
menwomen
NF 1823858.1101325
NF 1621206.1101325
kg g
Hole small enough, molecule passes as individual (not like fluid)
Effusion Effusion
When there is no hole Collision with wall A Area
() 14
number of molecules in Vol with velocity v to vdv
zyx dvdvdvvg V NAvdvg
V NA yy vv
V NA
Number of molecules Striking area A (with period of time )
avgv V NA
Proportional to area A Proportional to time Proportional to density Proportional to average speed
Rate = number of molecules striking unit area per unit time
avgv V Nmoleculev
P V NN
P V ON
2 10660.132
sm m
s/1044.1 23
Quite busy
m pH 2
Assume volume changes due to z0 completely
Define B
VI. The kinetic theory of gasesVI. The kinetic theory of gases
() 2
vgvvf 24
Most probable speed
048 2 dv
kgm 2710660.195.39
VIVI--3. Pressure, effusion and collision 3. Pressure, effusion and collision
yvVelocity after time
y
V NAyv
v to vdv
A Area
Total pressure
menwomen
NF 1823858.1101325
NF 1621206.1101325
kg g
Hole small enough, molecule passes as individual (not like fluid)
Effusion Effusion
When there is no hole Collision with wall A Area
() 14
number of molecules in Vol with velocity v to vdv
zyx dvdvdvvg V NAvdvg
V NA yy vv
V NA
Number of molecules Striking area A (with period of time )
avgv V NA
Proportional to area A Proportional to time Proportional to density Proportional to average speed
Rate = number of molecules striking unit area per unit time
avgv V Nmoleculev
P V NN
P V ON
2 10660.132
sm m
s/1044.1 23
Quite busy
m pH 2
Assume volume changes due to z0 completely
Define B