Knowing that ΔH_vap for water is 40.7 kJ/mol, calculate P_vap of water at 37°C. A) 12.4 torr B) 52.6 torr C) 18.7 torr D) 6.90 torr E) 25.4 torr

Question

Quizplus · Accepted Answer

The Clausius-Clapeyron equation can be used to relate the enthalpy of vaporization (ΔH) to the vapor pressure (P) of a substance at two different temperatures (T1 and T2):

ln(P1/P2) = (ΔH/R) * (1/T2 - 1/T1)

where R is the gas constant.

We can use this equation and the given enthalpy of vaporization for water to solve for the vapor pressure at 37°C (310 K). We can choose a reference temperature of 0°C (273 K) for P1, at which the vapor pressure of water is 4.58 torr.

ln(P/4.58) = (40.7 kJ/mol / 8.314 J/mol*K) * (1/273 K - 1/310 K)

Solving for P gives: P ≈ 52.6 torr

Therefore, the correct answer is B.

Knowing That ΔHvap for Water Is 40

Knowing That ΔH_vap for Water Is 40