Problem: The molar enthalpy of vaporization (∆H) of water is 40.7 kJ/mol. What is the vapor pressure of water at 40.°C (R=8.314J/K mol)?A) 11.5 torrB) 311 torrC) 3.58 torrD) 38.6 torrE) 61.4 torr

🤓 Based on our data, we think this question is relevant for Professor Sadeghi's class at UTSA.

FREE Expert Solution

We’re being asked to determine the vapor pressure of water at 40°C. We’re given the heat of vaporization of water ΔHvap = 40.7 kJ/mol. 


We can use the Clausius-Clapeyron Equation to solve for the vapor pressure of water.


ln P2P1=-HvapR[1T2-1T1]


where:

P1 = vapor pressure at T1

P2 = vapor pressure at T2

ΔHvap = heat of vaporization (in J/mol)

R = gas constant (8.314 J/mol•K)

T1 and T2 = temperature (in K).


View Complete Written Solution
Problem Details

The molar enthalpy of vaporization (∆H) of water is 40.7 kJ/mol. What is the vapor pressure of water at 40.°C (R=8.314J/K mol)?

A) 11.5 torr

B) 311 torr

C) 3.58 torr

D) 38.6 torr

E) 61.4 torr