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Description

Graham's Law states that a gas's rate of diffusion or effusion is inversely proportional to the square root of its molar mass. In simple terms, lighter gases move faster than heavier ones. This relationship comes from the fact that all gases at the same temperature have the same average kinetic energy, meaning a lighter molecule must move faster to have the same energy as a heavier one. The law's formula allows us to predict the relative speeds of gases. This principle applies to both diffusion (a gas spreading out) and effusion (a gas escaping through a small opening).