Determine the vapor pressure (in torr)of a substance at 36°C,whose normal boiling point is 84°C and has a ΔH_vapof 22.1 kJ/mol. A) 239 torr B) 31.8 torr C) 41.8 torr D) 147 torr E) 98 torr

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The Clausius-Clapeyron equation can be used to estimate the vapor pressure at a temperature given the enthalpy of vaporization and the normal boiling point. The equation in logarithmic form is: ln(P2/P1) = -ΔHvap/R * (1/T2 - 1/T1), where P1 is the vapor pressure at the normal boiling point (760 torr), T1 is the normal boiling point in Kelvin, P2 is the vapor pressure at the desired temperature, T2 is the desired temperature in Kelvin, ΔHvap is the enthalpy of vaporization, and R is the gas constant (8.314 J/mol·K, but we need to use the value in the correct units to match ΔHvap, so we use 8.314 J/K·mol * 10^-3 to convert to kJ/mol·K). Converting temperatures to Kelvin and solving for P2 gives the vapor pressure at 36°C.

Determine the Vapor Pressure (In Torr)of a Substance at 36°C,whose