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Vaporization. Vaporization. Evaporation in an open container. Condensation rate will probably never be as high as evaporation rate. Vaporization. Vaporization. Evaporation in a closed container. Condensation rate will eventually equal evaporation rate. Vaporization.
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Vaporization Evaporation in an open container. Condensation rate will probably never be as high as evaporation rate.
Vaporization Evaporation in a closed container. Condensation rate will eventually equal evaporation rate.
What factors affect the rate of evaporation? Temperature Surface area Strength of intermolecular attractive forces
What factors affect equilibrium vapor pressure? Temperature Strength of intermolecular attractive forces
An Exponential Equation for Pressure • P = β exp(-ΔHvap /RT) • ln P = ln β + ln exp(-ΔHvap / RT) • ln P = ln β - ΔHvap / RT • ln P = ln β - (ΔHvap / R) (1 / T) • Y = b + mX • Plot ln P against 1 / T. Slope = -ΔHvap/R • ΔHvap = -R . Slope where R = 8.314 J / K mol
The 2-Point Clausius-Clapeyron Equation • ln P = ln β - (ΔHvap / R) (1 / T) • ln P2 = ln β - (ΔHvap / R) ( 1 / T2) • Ln P1 = ln β - (ΔHvap / R) (1 / T1) • ln P2 - ln P1 = (ΔHvap / R) (1 / T1 - 1 / T2) • Ln (P2 / P1) = (ΔHvap / R) (1 / T1 - 1 / T2)