Name Experiment 10 Enthalpy of Vaporization Liquid n-pentane n-hexane The Clausius-Clapeyron Equation can be conveniently used in a two-point form, by subtracting to remove the integration constant: Data Point 1: n-heptane

n-octane CM1001 Post-Laboratory Assignment n-propanol acetone Show calculations: In(P₁) - In(P₂) = -Data Point 2: -In(P₂) = In(P₁): Formula C5H₁2 C6H₁4 C₂H16 C₂H₁8 C₂H₂OH CH3COCH = atm Section -Hvap RT₁ MW, g/mol 72.10 86.18 100.21 114.23 60.09 58.08 To predict the vapor pressure at a desired temperature, the only data needed is AHvap and the b.p. Recall that the normal boiling point (b.p.) is the temperature at which the vapor pressure = 1 atm, and can be used as T₁, P₁ in the above equation. Table 3 +C -Hvap RT₂ + c) 1 1 (Avap) (-²) = n(12) In R b.p., °℃ 36.1 68.7 98.5 125.7 97.1 56.1 Fall 2023 1. Use the data on Table 3 to calculate the following vapor pressures at 46.0 °C: a. Acetone v.p. @ 46.0 °C b. n-hexane v.p. @ 46.0 °C AHvap (kJ/mol) 25.8 28.9 31.7 35.0 47.2 30.3 atm