Benzene has a heat of vaporization of 30.72 kj/mol and a normal boiling point of 80.1 degrees celcius.

At what temperature does Benzene boil when the external pressure is 440 torr?

2 answers

Use the Clausius-Clapeyron equation.

ln(P2/P1) = -dHvap/R * (1/T2- 1/T1)

At the normal boiling point T1, the vapor pressure P1 is 760 torr. A lower temperature T2 will lower the vapor pressure to 440 torr.
112