Transcript Vaporization

Vaporization
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.
Vaporization
Vaporization
What factors affect the rate of
evaporation?
How Temperature Affects
Evaporation Rate
What factors affect the rate of
evaporation?
Temperature
Surface area
Strength of intermolecular
attractive forces
What factors affect equilibrium
vapor pressure?
What factors affect equilibrium
vapor pressure?
Temperature
Strength of intermolecular
attractive forces
Boiling
Boiling
An Exponential Equation for
Pressure
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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
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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)