Derive an expression that shows how the pressure of a gas inside an effusion oven (a heated chamber with a small hole in one wall) varies with time if the oven is not replenished as the gas escapes. Then show that t1/2, the time required for the pressure to decrease to half its initial value, is independent of the initial pressure. Hint: Start from the expression for the rate of effusion and rewrite it as a differential equation relating dp/dt to p; recall that pV = NkT can be used to relate the pressure to the number density.

Derive an expression that shows how the pressure of a gas inside an effusion oven (a heated chamber with a small hole in one wall) varies with time if the oven is not replenished as the gas escapes. Then show that t1/2, the time required for the pressure to decrease to half its initial value, is independent of the initial pressure. Hint: Start from the expression for the rate of effusion and rewrite it as a differential equation relating dp/dt to p; recall that pV = NkT can be used to relate the pressure to the number density.

Physical Chemistry

2nd Edition

ISBN:9781133958437

Author:Ball, David W. (david Warren), BAER, Tomas

Publisher:Ball, David W. (david Warren), BAER, Tomas

Chapter1: Gases And The Zeroth Law Of Thermodynamics

Section: Chapter Questions

Problem 1.32E

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