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Kinetic Theory — Effusion & Graham's Law

Gas escaping through a tiny hole — lighter molecules escape faster, rate ∝ 1/√mass (Graham 1848)

Two-Compartment Box
Escape Count Over Time
Light escaped: 0 | Heavy escaped: 0 | ratio: —
Maxwell-Boltzmann: at temperature T, mean speed v̄ = √(8kT/πm). Graham's Law: effusion rate ∝ 1/√m. Light molecules (He-like, orange) in left; heavy (N₂-like, blue) in right. Expected ratio of escape rates = √(m_heavy/m_light). Watch the predicted ratio match Graham's Law as statistics accumulate.