CHEM 161 – 01 CHAPTER 11 Homework 3 Vapor Pressure

CHEM 161 – 01CHAPTER 11Homework 3Vapor PressureName:_________________________________Due Tuesday January 26 2016Work the following problems on your own paper. Please staple your pages together before handing theproblem set in. Each problem is worth 5 points for a maximum of 25 points. Each problem is gradedholistically on a scale of 0 – 5 based on accuracy and completeness.1. Answer each of the following questions with increase decrease or does not change.a.b.c.d.If the intermolecular forces in a liquid increase the normal boiling point of theliquid ________.If the intermolecular forces in a liquid decrease the vapor pressure of theliquid _______.If the surface area of a liquid decreases the vapor pressure ________.If the temperature of a liquid increases the vapor pressure ________.2. The following table gives the equilibrium vapor pressure of benzene C 6H6 at varioustemperatures:Temperature (C)7.626.160.680.1Vapor Pressure (mmHg)40.0100.0400.0760.0Use Excel© or some other spreadsheet to graphically (plot ln(p) versus 1/T (Kelvin))determine: 1) the molar enthalpy of vaporization of (?Hvap) benzene and 2) the vaporpressure of benzene at 50.0 C. (You must turn in this graph to get full credit for thisproblem.)3. The normal boiling point of ethanol CH3CH2OH is 78.3C and its molar heat ofvaporization (?Hvap) is 39.3 kJ/mol. What would be the vapor pressure in Torr ofethanol at 32.0C?4. Carbon disulfide CS2 has a vapor pressure of 100 mmHg at -5.1 C and a normal boilingpoint of 46.5 C. What is the molar enthalpy of vaporization (Hvap) for carbon disulfidein kJ/mol? What is the vapor pressure of carbon disulfide (in mm Hg) at 20.0 C?5. Water (H2O) has a molar enthalpy of vaporization (Hvap) of 40.7 kJ/mol; and its normalboiling point is 100.0 °C. What temperature (°C) does water boil in a pressure cookerwhen the internal pressure of the cooker is 1.90 atm?