A certain liquid has a vapor pressure of 92.0 Torr at 23.0 ∘C and 274.0 Torr at 45.0 ∘C.

Answer 1

What's the question? Are you asking to find the ∆Hvap? I'll assume that's the question.

This would require use of the Clausius Clapeyron equation:

ln (P2/P1) = -∆Hvap/R (1/T2 - 1/T1)

P1 = 92.0 torr

P2 = 274 torr

R = 8.314 J/Kmol

T1 = 23ºC + 273 = 296K

T2 = 45ºC + 273 = 318K

∆Hvap = ?

ln (274/92) = -∆Hvap/8.314 (1/318 - 1/296)

1.09 = -∆Hvap/8.314 (0.00314 - 0.00338)

1.09 = 0.00024∆Hvap / 8.314

∆Hvap = 37,759 J/mol = 37.8 kJ/mol

(be sure to check the math)