1
1.(6 pts) The pressure exerted by a column of liquid is equal to the product of the height
of the column times the gravitational constant times the density of the liquid. How
high a column of water (d = 1.0 g/mL) would be supported by a pressure that supports
a 713 mm column of mercury (d = 13.6 g/mL)?
a) 14 mm
b) 52 mm
c) 713 mm
d) 1.2 x 104 mm
e) 9.7 x 103 mm
2.(5 pts) Of the following, _____ is a valid statement of Charles’ law.
a) P/T = constant
b) V/T = constant
c) PV =const
d) V = constant x n
e) V = constant x P
3. (5 pts) A sample of gas occupies 10.0 L at 50C. Assuming that pressure is constant, what volume in L will the gas occupy at 100C?
a) 10.0 b) 20.0 c) 11.5 d) 5.0 e) 8.7
4. (5pts) At what temperature (in °C) will 25.0 g of carbon dioxide, CO2, (at 1.00 atm) occupy 21.5 L?
a) 188 b) 461 c) -263 d) -270 e) 113
5. (6 pts) What is the molar mass of a gas that has a density of 3.11 g/L at 100C and 1.50 atm pressure?
a) 0.152 b) 95.2 c) 17.0 d) 63.5 e) 54.2
6. (7 pts) What volume of N2 gas (in L) would be produced by the decomposition of 35.0 g NaN3 solid? (Assume that the gas is produced at 1.00 atm pressure and 150C.) The reaction is as follows:
2NaN3(s) → 2Na (s) + 3N2(g)
a) 28.0 b) 9.95 c) 18.7 d) 56.1 e) 30.4
7. (7 pts) At what temperature in K would CO2 gas have the same average molecular speed as O2 gas has at 400 K?
a) 59 b) 98 c) 250 d) 550 e) 400
8. (6 pts) How much faster does nitrogen escape from a balloon than oxygen?
a) 1.07 b) 0.635 c) 1.14 d) 0.875 e) 0.935
9. (7 pts) Using the van der Waals equation, P = nRT - n2a , the pressure in a 22.4 L
V-nb V2
vessel containing 1.00 mol of neon gas at 100oC is _____ atm.
( a = 0.211 L2 – atm/mol2; b= 0.0171 L/mol). R = 0.08206 L-atm
mol-K
a) 0.730 b) 1.00 c) 1.21 d) 1.37 e) 0.367
10 (5 pts) Which one of the following exhibits dipole-dipole attraction between molecules?
a) XeF4 b) AsH3 c) CO2 d) BCl3 e) Cl2
11. (5 pts) Based on molecular mass and dipole moment of the five compounds in the table below, which should have the highest boiling point?
Substance Molecular Mass (amu) Dipole moment (D)
I. Propane, CH3CH2CH3 44 0.1
II. Dimetylether, CH3OCH3 46 1.3
III. Methylchloride, CH3Cl 50 1.9
IV.Acetaldehyde, CH3CHO 44 2.7
V. Acetonitrile, CH3CN 41 3.9
a) I b) II c) III d) IV e) V
12. (5 pts) Which one of the following derivatives of ethane has the highest boiling point?
a) C2Br6 b) C2F6 c) C2I6 d) C2Cl6 e) C2H6
13. (5 pts) Of the following substances, only ____ has London dispersion forces as its only intermolecular force.
a) CH3OH b) NH3 c) H2S d) CCl4 e) HCl
14.(5 pts) The intermolecular force(s) responsible for the fact that CH4 has the lowest boiling point in the set CH4, SiH4, GeH4, SnH4 is/are ______.
a) hydrogen bonding
b) dipole-dipole interactions
c) London dispersion forces
d) mainly hydrogen bonding but also dipole-dipole interactions
e) mainly London-dispersion forces but also dipole-dipole interactions
15. (5 pts) Which of the following should have the lowest boiling point?
a) PH3 b) H2S c) HCl d) SiH4 e) H2O
16. (5 pts)______is the energy required to expand the surface area of a liquid by a unit amount of area.
a) viscosity b) surface tension c) volatility d) meniscus e) capillary action
17. (5 pts) The substance with the largest heat of vaporization is ______.
a) I2 b) Br2 c) Cl2 d) F2 e) O2
18. (7 pts) Ethanol (C2H5OH) melts at -114oC and boils at 78oC. The enthalpy of fusion of ethanol is 5.02 kJ/mol, and its enthalpy of vaporization is 38.56 kJ/mol. The specific heats of solid and liquid ethanol are 0.97 J/g-K and 2.3 J/g-K, respectively. How much heat (in kJ) is required to convert 75.0 g of ethanol at -120oC to the vapor phase at 78oC?
a) 105 b) 65.6 c) 20.9 d) 204 e) 89.7
19.(5 pts) The slope of a plot of the natural log of the vapor pressure of a substance versus 1/T is _____.
a) ∆Hvap b) - ∆Hvap c) 1/∆Hvap d) -∆Hvap /R e) -1/∆Hvap
20.(5 pts) The critical temperature and pressure of CS2 are 279oC and 78 atm, respectively. At temperatures above 279oC, CS2 can only occur as a ______.
a) solid b) liquid c) liquid and gas d) gas e) supercritical fluid
21. (5 pts) The phase diagram of a substance is given below. The region that corresponds to the solid phase is ______.
a) w b) x c) y d) z e) x and y
22.(6 pts) An element crystallizes in a body-centered cubic lattice. The edge of the unit cell is 2.86 Å and the density of the crystal is 7.92 g/cm3. What is the atomic weight of the element? Avogadro’s number is 6.02 x 1023 atoms/mol.
a) 55.8 b) 98.7 c) 23.6 d) 22.9 d) 103
23. (6 pts) A solution contains 10% ethanol, 25% butanol, 40% propanol, and 25% methanol. The solvent is ______. All compositions are mass percentages.
a) ethanol b) methanol c) butanol d) propanol e) none of these
24. (5 pts) Which one of the following would be the most soluble in CCl4?
a) CH3CH2OH b) H2O c) NH3 d) C10H22 e) NaCl
31. (7 pts) The concentration of nitrogen gas in water is ____ M when the partial pressure of N2 above the solution is 0.826 atm. Henry’s law constant for this system is 6.8 x 10-4
mol/L-atm.
a) 5.6 x 10-4 b) 1.2 x 10-4 c) 8.2 x 10-3 d) 0.43 e) 5.6
25.(6 pts) The concentration of chloride ion (mass %) in a solution that contains 35.0 ppm chloride is ____%.
a) 3.5 x 10-3 b) 3.50 x 102 c) 3.50 x 10-2 d) 3.50 x 10-6 e) 3.50 x 101
26. (7 pts) Calculate the molarity, molality, and mole fraction of methanol (CH3OH) in a solution composed of 26.5 g CH3OH and 244 g water. (Assume that the density of the solution is 0.975 g/mL)
a) 2.98 x 10-3, 3.06, 0.0611
b) 2.98, 3.39, 0.0575
c) 2.98, 3.39, 0.0611
d) 2.98, 3.06, 0.0575
e) 2,98, 3.06, 0.0611
27. (7 pts) Glycerin (C3H8O3) is a nonvolatile nonelectrolyte with a density of 1.26 g/mL at 25oC. Calculate the vapor pressure at 25oC (in torr) of a solution made by adding 50.0 mL of glycerin to 500.0 mL of water. The vapor pressure of pure water at 25oC is 23.8 torr. (Hint: Use Raoult’s law). Assume that the density of water is 1.00 g/mL
a) 23.8 b) 25.0 c) 22.1 d) 23.2 e) 18.0
28. (7 pts) Automotive antifreeze consists of ethylene glycol (C2H6O2), a nonvolatile nonelectrolyte. Calculate the boiling point and freezing point ( in oC) of a 25.0% mass% solution of ethylene glycol in water. The Molal-Boiling Point-Elevation Constant for water (Kb) is 0.51oC/m and the Freezing-Point Depression Constant for water (Kf) is
1.86 oC/m.
a) 104.0; 0.00 b) 102.7; -10.0 c) 105.0; -15.0 d) 104.0; -11.0 e) 103.8; -12.0
29.(6 pts) The average osmotic pressure of blood is 7.7 atm at 25oC. What concentration of glucose (C6H12O6) in moles/L will be isotonic with blood?
a) 0.31 b) 0.50 c) 0.46 d) 0.25 e) 0.14
30. (7 pts) A solution is prepared by dissolving 2.60 g of a strong electrolyte (formula weight = 101 g/mol) in enough water to make 1.00 L of solution. The osmotic pressure of the solution is 1.25 atm at 25.0 oC. What is the van’t Hoff factor (i) for the unknown solute?
a) 0 b) 0.99 c) 1.99 d) 2.98 e) 0.630
Numerical Values of the Gas Constant, R, in Various Units
Units Numerical Values
L-atm 0.08206
mol-K
J 8.314
mol-K
kg-m2 8.314
s2mol-K