Reading assignment: 21.1
In the molecular model of ideal gases, what is it that causes a gas to exert
pressure on its surroundings?
Pressure gets exerted by collisions of the gas molecules with the walls. Each collision exerts a tiny amount of force; when all the collisions are added up, the result is a macroscopic force which is the pressure times the area.
What is it that causes a gas to have a certain temperature?
Temperature is a measure of the average translational kinetic energy of a molecule. "Hotter" gases are ones where the molecules have a lot of energy, on average, which they can impart to other objects thus warming them up.
Compare vrms for various gases given in Table 21.1 to the speed of
sound given in Table 17.1. Is there a connection? Why/why not?
It seems like there is a clear correlation: the gases with higher v_rms's also have faster sound velocities. This is because a sound wave actually gets transported by the gas molecules themselves.
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