Mean Time Between Collisions of Ideal Gas Molecules: What Factors Matter?

AI Thread Summary
The mean time between collisions of ideal gas molecules is influenced primarily by number density and temperature. While molecular size is typically assumed negligible in ideal gas theory, the density of molecules plays a crucial role in collision frequency. Temperature affects the average kinetic energy of the molecules, which in turn influences their speed and collision rate. The discussion suggests that, for an ideal gas, the mean time between collisions may depend more on temperature than on molecular size or density due to the assumption of non-interacting particles. Overall, the relationship between these factors is complex and warrants further exploration for precise formulas.
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If one considers an ideal gas, what does the mean time between collissions of the molecules depend upon? molecular size? number per unit volume? temperature of the gas?

I'm thinking so far, it must def depend on number density. It would usually depend on molecular size (but I thought an ideal gas was supposed to assume point like particles?). It may not depend on temperature since n=PV/RT, so if you specifically number density then perhaps you already factored in temperature dependence?

Anyone know any specific formula for this mean time of flight or how to derive?
 
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or perhaps it does depend on temperature because the particles have higher K.E and faster speeds on average?
 
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I'm thinking now time of flight only depends on temp not density or size for an ideal gas because they don't interact, and the temp is just entering into the v_rms for when they collide with walls is less?
 
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