Gases : Graham's Laws of Diffusion and Effusion 

Graham's Law of Diffusion
 The rate at which gases diffuse is inversely proportional to the square root of their densities.
Graham's Law of Effusion
 The rate of effusion of a gas is inversely proportional to the square root of either the density or the molar mass of the gas.
The time required for 25mL samples of different gasses to diffuse through a pinhole into a vacuum. 
The Kinetic Molecular Theory and Graham's Law
 Since KE_{avg} is dependent only upon T, two different gases at the same temperature must have the same KE_{avg}.
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