The vapor pressure of ethanol is 400. mmHg at 63.5°C. Its molar heat of vaporization is 39.3 kJ/mol. What is the vapor pressure of ethanol, in mmHg, at 34.9°C? (R = 8.314 J/K • mol)
A) 109 mmHg
B) 220 mmHg
C) 366 mmHg
D) 376 mmHg
E) 1470 mmHg

Question

Quizplus · Accepted Answer

Using the Clausius-Clapeyron equation, we can calculate the vapor pressure at a different temperature. The equation is: ln(P2/P1) = -ΔHvap/R * (1/T2 - 1/T1). Converting temperatures to Kelvin and using the given values, the calculation shows that the vapor pressure at 34.9°C is approximately 109 mmHg.

The Vapor Pressure of Ethanol Is 400