CH 222 WINTER 2011 - SECOND MIDTERM EXAM

This exam has 22 questions worth 5 pts each, plus one question worth 2 pts.The total possible score is 112 pts.

DO NOT OPEN THIS EXAM UNTIL TOLD TO DO SOBefore the exam begins you can do the following on the Scantron answer sheet. Use a #2 pencil.

1. Fill in your name (LAST NAME, FIRST NAME) in the large box on the left. Don't forget to bubble in the circles below your name.

2. Fill in your student ID number in the box labeled "IDENTIFICATION NUMBER". Do not use dashes or blank spaces. Fill in the circles as well.

3. In the box labeled "CLASS SECTION NUMBER", enter the appropriate number

8 am class = section 001 (Nafshun) 9 am class = section 002 (Nafshun)11am class = section 003 (Watson) 12pm class = section 050 (Muir)

4. In the lower right corner, in the box labeled "FORM NUMBER", write in the exam form number (1, 2, 3, 4 etc.) given above in the shaded box and fill in the bubble.

ONLY ONE APPROVED NOTECARD IS ALLOWED

ALL PHONES AND OTHER ELECTRONIC DEVICES OTHER THAN CALCULATORS MUST BE OFF

You may keep this exam packet and your notecard when the exam period is complete.

Hand in the Scantron answer sheet to a TA at the end of the exam.

Form No. 3

Periodic Table

1 m = 1 x 1012 pm1 m = 100 cmFor Simple Cubic: l = 2rFor BCC: l = 4r/√3For FCC: l = 4r/√2

R = 0.0821 L•atm/mol•K 760 mm Hg = 760 torr = 1 atm m = mol/kgM = mol/L ΔTf = imkf ΔTb = imkb

ΠV = nRT kf (H2O) = 1.86 ºC/m kb(H2O) = 0.512 ºC/m1. Which of the following statements about ideal gases is NOT TRUE?

(A)A sample of ideal gas kept at constant pressure that is cooled from 100 °C to 50 °C will halve its volume.

(B) An ideal gas has no interactions between its molecules.(C) An ideal gas obeys the equation (T/P) = (V / nR)(D)An ideal gas has zero volume at 0 K.(E) A sample of an ideal gas will double in volume if its pressure is halved at constant temperature.

2. A student measures the pressure inside their home to be 0.981 atm. How high would the column of mercury be in a barometer?

(A) 0.00129 mm(B) 746 mm(C) 1.29 mm(D) 9.81 mm(E) 981 mm

3. 1.55 grams of a gas exerts a pressure of 1.0 atm in a volume of 2.24 L at 300 K. What is a possible identity of the gas?

(A) ammonia (NH3)(B) carbon dioxide (CO2)(C) carbon monoxide (CO)(D) hydrofluoric acid (HF)(E) carbon disulfide (CS2)

4. A balloon initially filled to 1.0 L has a pressure of 1.34 atm. A student reduces the volume until the pressure is 1.67 atm.  What is the final volume of the balloon?

(A)       0.340 L(B)       1.25 L(C)       0.802 L(D)       2.24 L(E)       3.01 L

5. Shown below is the balanced equation for the combustion of butane. What is the volume (liters) of CO2 (g) produced at 1.500 atm and 298.0 K from the combustion of 100.0 g of butane in excess O2 (g)?

2 C4H10 (g) + 13 O2 (g) 8 CO2 (g) + 10 H2O (g)

(A) 125.5 L(B) 28.08 L(C) 112.3 L(D) 224.0 L(E) 149.3 L6. A syringe contains 589 mL of CO at 325 K and 1.2 atm pressure. A second syringe contains

473 mL of N2 at 298 K and 2.6 atm. What is the final pressure if the contents of these two syringes are injected into a 1.00 L container at STP?

(A) 0.59 atm(B) 1.1 atm(C) 1.7 atm(D) 1.9 atm(E) 3.8 atm

7. In an experiment, 225 mL of wet H2 is collected over water at 27 °C and a barometric pressure of 748 torr. How many grams of Zn have been consumed? The vapor pressure of water at 27°C is 26.7 torr.

(A) 588 g(B) 0.567 g(C) 567 g(D) 0.431 g(E) 0.588 g

8. Consider the Van der Waals equation:

Which of the following is FALSE?

(A) The Van der Waals equation accounts for the actual size of the gas molecules.(B) The Van der Waals equation accounts for dispersion between the gas molecules.(C) The Van der Waals equation accounts for hydrogen bonding in water vapor.(D) The Van der Waals equation accounts for the variations of the molar volumes of real

gases.(E) The Van der Waals equation accounts for the temperature dependence of molar mass.

9. Referring to the figure below, select the statement that is CORRECT.

(A) Molecules of A have higher average velocities than molecules of B.(B) If A and B are at the same temperature, then A molecules are lighter than B molecules.(C) If A and B have the same mass, then A molecules are at a higher temperature than B molecules.(D) All the above statements are incorrect.

10. Based on the figure below, which liquid has a boiling point of 60 ºC under an external pressure of 350 Torr?

(A) diethyl ether(B) ethyl alcohol(C) water(D) ethylene glycol(E) none of the above

11. Define deposition.

(A) the phase transition from solid to gas(B) the phase transition from gas to solid(C) the phase transition from gas to liquid(D) the phase transition from liquid to gas(E) the phase transition from liquid to solid

12. How much energy is required to vaporize 158 g of butane (C4H10) at its boiling point, if its ΔHvap is 24.3 kJ/mol?

(A) 15.1 kJ(B) 66.1 kJ(C) 89.4 kJ(D) 11.2 kJ(E) 38.4 kJ

13. Give the net ionic equation for the reaction (if any) that occurs when aqueous solutions of K2S and Fe(NO3)2 are mixed.

(A) K+(aq) + NO3-(aq) → KNO3(s)(B) Fe2+(aq) + S2-(aq) + 2 K+(aq) + 2 NO3-(aq) → FeS(s) + 2 K+(aq) + 2 NO3-(aq)(C) Fe2+(aq) + S2-(aq) + 2 K+(aq) + 2 NO3-(aq) → Fe2+(aq) + S2-(aq) + 2 KNO3(s)(D) Fe2+(aq) + S2-(aq) → FeS(s)(E) No reaction occurs.

14. What are the concentrations of Fe3+ ions and sulfate ions in 0.5 M Fe2(SO4)3 (aq) ?

(A) 0.5 M and 0.5 M(B) 1.0 M and 0.5 M(C) 1.0 M and 1.5 M(D) 0.5 M and 1.5 M(E) 1.5 M and 1.0 M

15. Which of the following compounds will be most soluble in pentane (C5H12)?

(A) pentanol (CH3CH2CH2CH2CH2OH)(B) benzene (C6H6)(C) acetic acid (CH3CO2H)(D) ethyl methyl ketone (CH3CH2COCH3)(E) None of these compounds should be soluble in pentane.

16. Choose the aqueous solution that has the highest boiling point. These are all solutions of nonvolatile solutes and you should assume ideal van't Hoff factors where applicable.

(A) 0.100 m AlCl3(B) 0.100 m NaCl(C) 0.100 m MgCl2(D) 0.100 m C6H12O6(E) They all have the same boiling point.

17. The cubic form for the fictitious element Rainium is BCC. The atomic radius is161.2 pm and the molar mass is 233.7 g/mol. The density of Rainium is:

(A) 15.0 g/cm3

(B) 24.8 g/cm3

(C) 22.8 g/cm3

(D) 26.8 g/cm3

(E) 20.7 g/cm3

18. The four solids below are listed as 1, 2, 3, and 4. Correctly identify the four solids.

(A) 1 is a bcc structure; 2 is diamond; 3 is graphite; 4 is NaCl(B) 1 is NaCl; 2 is diamond; 3 is graphite; 4 is a bcc structure(C) 1 is NaCl; 2 is graphite; 3 is diamond; 4 is a bcc structure(D) 1 is a bcc structure; 2 is graphite; 3 is diamond; 4 is NaCl(E) 1 is NaCl; 2 is a bcc structure; 3 is graphite; 4 is diamond

19. Consider acetone, CH3COCH3. The intermolecular forces present in CH3COCH3 are:

acetone

(A) Dispersion forces only(B) Dipole-dipole forces only(C) Dispersion forces and dipole-dipole forces(D) Dispersion forces, dipole-dipole forces, and hydrogen bonding(E) Hydrogen bonding only

20. A student places 360.3 grams of molecular glucose, C6H12O6 into 3.00 kg of water. The freezing point of this solution is:

(A) - 1.24 C(B) - 2.45 C(C) - 4.56 C(D) - 13.7 C(E) - 9.11 C

21. The intermolecular forces that are most significant in accounting for the high boiling point of liquid water relative to other substances of similar molecular weight is/are the:

(A) Dispersion forces(B) Dipole-dipole interactions(C) Hydrogen bonding(D) Network covalent forces(E) Ionic charges

22. Consider He, CH4, diamond, CH3CH2OH, LiCl, and CH3OCH3. Arranged in increasing melting point, these are:

Lowest mp Highest mp(A) He < diamond < CH3CH2OH < CH3OCH3 < CH4 < LiCl (B) He < CH4 < CH3CH2OH < LiCl < CH3OCH3 < diamond(C) CH4 < He < CH3CH2OH < CH3OCH3 < LiCl < diamond(D) CH4 < He < CH3CH2OH < CH3OCH3 < diamond < LiCl(E) He < CH4 < CH3OCH3 < CH3CH2OH < LiCl < diamond

23. The final exam is:

(A) Wednesday, March 16, 2011 at 7:30am (Good Morning!)(B) Wednesday, March 16, 2011 at 7:30am (Good Morning!)(C) Wednesday, March 16, 2011 at 7:30am (Good Morning!)(D) Wednesday, March 16, 2011 at 7:30am (Good Morning!)(E) Wednesday, March 16, 2011 at 7:30am (Good Morning!)