The normal boiling point of acetic acid, HC₂H₃O₂, is 117.9°C, and its heat of vaporization is 39,690 J/mol. What is its vapor pressure at 100.0°C?

Question

Quizplus · Accepted Answer

The Clausius-Clapeyron equation can be used to calculate the vapor pressure of a liquid at a given temperature:ln(P2/P1) = -ΔHvap/R * (1/T2 - 1/T1)where P1 and T1 are the known vapor pressure and temperature, P2 is the unknown vapor pressure, T2 is the new temperature, ΔHvap is the heat of vaporization, and R is the gas constant.Plugging in the given values:ln(P2/760 torr) = -39,690 J/mol / (8.314 J/mol*K) * (1/373.15 K - 1/393.15 K)Solving for P2:P2 = 423.2 torrTherefore, the vapor pressure of acetic acid at 100.0°C is 423.2 torr.

The Normal Boiling Point of Acetic Acid, HC2H3O2, Is 117

The Normal Boiling Point of Acetic Acid, HC₂H₃O₂, Is 117