Chemistry 116: General Chemistry

Syracuse University Project Advance

Final Exam, Spring 2007

Name Date

The last page of this exam is a periodic Table

[Gas constant = 8.314J/mol K; 1 faraday = 96,500 J/V mol e- y]

1. Which of the reactants and/or products do not appear in the properly written Kc expression

for the heterogeneous reaction

NiCO3 (s) + 2H+ (aq) ßà Ni+2 (aq) + CO2 (g) + H2O (l) ?

A NiCO3 (s)

B. CO2 (g) + H2O (l)

C. H+ (aq) and Ni+2 (aq)

D. CO2 (g)

E. NiCO3 (s) and H2O (l)

2. What is the pH of a 0.25 M solution of HNO2 (Ka = 4.0 ´ 10-4)?

  1. 1.70
  2. 2.00
  3. 2.30
  4. 2.70
  5. 3.70

3. Given that Ksp = 1.0 ´ 10-12 for AgSCN (silver thiocyanate), what is its molar solubility?

  1. 2.0 ´ 10-12 M
  2. 1.0 ´ 10-10 M
  3. 2.0 ´ 10-10 M
  4. 1.0 ´ 10-6 M
  5. 2.0 ´ 10-6 M

4. The average rate of disappearance of ozone in the reaction 2O3 (g) 3O2 (g) was found to be 7.0 ´ 10-3 atm/sec over a certain time interval. What is the rate of appearance of O2 during this interval?

  1. 1.0 ´ 10-2 atm/sec
  2. 7.0 ´ 10-3 atm/sec
  3. 5.0 ´ 10-3 atm/sec
  4. 3.0 ´ 10-3 atm/sec
  5. 2.0 ´ 10-3 atm/sec

5. When undergoes electron capture, what nuclide is produced?

6. Which statement is true?
  1. Exothermic reactions are always spontaneous.
  2. Free energy is independent of temperature.
  3. At constant P and T, a decrease in free energy ensures an increase in the entropy of the system.
  4. A reaction that exhibits a negative value of DS cannot be spontaneous.
  5. None of the above statements is true.

7. The oxidation state of H in CaH2 is

  1. +2
  2. +1
  3. 0
  4. -1
  5. -2

8. Suppose the reaction 2 CO(g) <======> CO2(g) + C(s) is already at equilibrium. If we increased the pressure on the system

A. the reaction shifts to the left (more reactants)

B. the reaction shifts to the right (more products)

C. the reaction is unaffected.

9. For the reaction A + B ¾¾® C, the following data were obtained. What is the rate law?

Experiment / [A]o / [B]o / Initial Rate (M/sec)
1 / 0.10 / 0.20 / 0.03
2 / 0.20 / 0.20 / 0.059
3 / 0.20 / 0.30 / 0.060
4 / 0.30 / 0.30 / 0.089
5 / 0.30 / 0.50 / 0.091
  1. Rate = k[A]
  2. Rate = k[B]
  3. Rate = k[A][B]
  4. Rate = k[A]2[B]
  5. Rate = k[A][B]2

10. A solution that is formed by combining 400 mL of 0.30 M NaOH with 500 mL of 0.060 M HCl has a pH of

A.  1.0

B.  2.0

C.  3.0

D.  5.0

E.  7.0

11. Consider the following reaction, and assume ideal gas behavior:

2NOBr(g) 2NO(g) + Br2(g)

A 1.0-L vessel was initially filled with pure NOBr to 4.0 atm. After equilibrium was established at 300K, the partial pressure of NOBr was 2.5 atm. What is Kp for the reaction?

  1. 0.18
  2. 0.27
  3. 0.45
  4. 0.54
  5. 0.75

12 Given the following equation:

CO2(g) + C(s) <======> 2 CO(g) with Kc = 14.0 at 800° C

The equilibrium constant at 800° C

A. favors reactants

B. favors products

C. favors neither

D. can’t determine from the given data

13. 2-Ethylheptane is not a standard IUPAC name. The correct name for this compound is

  1. 3-ethylheptane.
  2. 2-pentylbutane.
  3. 3-pentylbutane.
  4. 2-methyloctane.
  5. 3-methyloctane.

14. For the reaction

DS˚ = -269 J/(mol.K)

DH˚ = -103.8 kJ/mol

Calculate the equilibrium constant at 25oC for the reaction above.

  1. 7.2 ´ 10-5
  2. 1.0
  3. 1.4 ´ 104
  4. 1.0 ´ 1017
  5. 3.7 ´ 1019

15 The equilibrium constant, Kp, for the reaction 2HgO (s) ßà 2Hg (l) + O2 (g) is 1.2 x 10-30.

Calculate the Kp for the reaction : ½ O2 (g) + Hg (l) ßà HgO (s)

A. 9.1 x 1014

B. 8.3 x 1029

C. 1.1 x 10-15

D. –1.1 x 1015

E. 4.2 x 1029

16. Which of the following is/are not a true statement?

(1) NH3 (aq) ( NH4OH (aq) ) is a base according to the Arrhenius, Bronsted-Lowrey and Lewis Concepts of acids and bases.

(2) The Bronsted-Lowrey conjugate acid to OH- (regarded as base) is H2O.

(3) In the following reaction: HPO42- + NH4+<======> H2PO4- + NH3, H2PO4- is a Bronsted-Lowrey base.

A. 1

B. 2

C. 2 and 3

D. 1 and 3

E. 3

17. The most stable allotrope of oxygen is

  1. O2
  2. O3
  3. H2O
  4. H2O2
  5. Fe2O3

18. The fusion reaction below has been of great interest as a potential energy source. How much energy is released in the fusion of one mole each of deuterium and tritium? (The speed of light is 2.9979 m/s. The masses of the atoms and neutron are shown below.)

2.0140 3.01605 4.002603 1.008665

amu amu amu amu

  1. 56.3 J
  2. 5.63 ´ 108 J
  3. 8.44 ´ 1011 J
  4. 1.69 ´ 1012 J
  5. 7.84 ´ 1044 J

19. What is the concentration of H3O+ in a solution of 0.075 M KOH at 25° C?

A. 0.075 M

B. 0.150 M

C. 1.33 x 10-13 M

D. 6.66 x 10-14 M

E. none of the above

20. At 760K, acetaldehyde decomposes to carbon monoxide and methane.

CH3CHO ¾¾® CH4 + CO

A plot of ln[CH3CHO] versus time was found to be linear, and it took 530 s for [CH3CHO] to decrease from an initial value of 0.10 M to 0.050 M. The rate law for the reaction is

21. What is the reducing agent in the following reaction?
3Cl2(g) + 2OH-(aq) + 2CrO42-(aq) + 2H2O(l) ¾¾® 6ClO-(aq) + 2Cr(OH)3(s)
  1. Cl2
  2. OH-
  3. CrO42-
  4. H2O
  5. ClO-

22. What is the minimum concentration of Mg2+ that is needed to begin the formation of a precipitate of Mg(OH)2 in a aqueous solution of pH = 10.0? (Ksp of Mg(OH)2 = 6 x 10-12).

A. 3 x 10-8 M

B. 3 x 10-4 M

C. 1.5 x 10-4 M

D. 6 x 10-8 M

E. 6 x 10-4 M

23. Which of the following mixtures is a buffer solution? (OAc = acetate ion shorthand C2H5O2 )

A. 10 mL of 1 M NaOH + 10 mL of 1 M HCl

B. 10 mL of 1 M NaOAc + 10 mL of 1 M NaCl

C. 10 mL of 1 M NaOH + 10 mL of 1 M HOAc

D. 10 mL of 1 M HOAc + 10 mL of 1 M NaOAc

E. 10 mL of 1 M HOAc + 20 mL of 1 M HCl

24. What is the pH of a 0.10 M NH3 solution? (Ka = 5.6 ´ 10-10 for NH4+.)

  1. 8.87
  2. 9.37
  3. 9.71
  4. 11.13
  5. 11.63

25. The heat of fusion of acetic acid is 11.5 kJ/mol. Its melting point is 16.6˚C. The change in entropy for the melting of acetic acid in J/(mol K) is (Hint: FLM)

  1. -11.5
  2. 11.5
  3. 15.1
  4. 39.7
  5. 694


26. Given the following standard electrode potentials:

Reaction E°

Li+ <======> Li -3.05

Cr3+ <======> Cr -0.740

Cu2+ <======> Cu 0.337

Which one of the reactions below will proceed spontaneously from left to right? (equations below are not necessarily balanced)

A. Cu + Li+ ------> Cu2+ + Li

B. Cr3+ + Cu2+ ------> Cr + Cu

C. Cr + Cu2+ ------> Cr3+ + Cu

D. Cu + Cr3+ ------> Cu2+ + Cr

E. None of the above

27. How many grams of copper metal can be obtained by passing a current of 12 amps through a

solution of CuSO4 for 15 minutes?

A. 0.016 g

B. 3.6 g

C. 7.1 g

D. 14 g

E. none of these

28. The reaction, 2A + B ¾¾® C, has the following proposed mechanism:

Step 1: A + B D (fast equilibrium)

Step 2: D + B ¾¾® E (slow)

Step 3: E + A ¾¾® C + B (fast)

If this mechanism is correct, the anticipated rate law is

  1. Rate = k[A]
  2. Rate = k[A][B]
  3. Rate = k[A]2[B]
  4. Rate = k[A][B]2
  5. Rate = k[A]2[B]2

29. Which of the following equations represents the Haber process?

  1. 2H2 + O2 ¾¾® 2H2O
  2. 2NO2 + 7H2 ¾¾® 2NH3 + 4H2O
  3. Fe2O3 + 2Al ¾¾® 2Fe + Al2O3
  4. Fe2O3 + 3H2 ¾¾® 2Fe + 3H2O
  5. 3H2 + N2 ¾¾® 2NH3

30. A sample of wood from an Egyptian mummy case was measured to have a 14C count of 9.4 cpm/gC (counts per minute per gram of carbon). How old is the wood? (The half-life of 14C is 5730 years, and the 14C count of living wood is 15.3 cpm/gC.)

  1. 2210 years
  2. 3520 years
  3. 4030 years
  4. 4570 years
  5. 6400 years

31. Given the reduction potentials,

Au3+ + 3e- ¾¾® Au E˚ = +1.50 V

Ni2+ + 2e- ¾¾® Ni E˚ = -0.23 V

What is DG˚ at 25˚C for the reaction:

2Au3+ + 3Ni ¾¾® 2Au + 3Ni2+

  1. -5.00 ´ 102 kJ/mol
  2. 5.00 ´ 102 kJ/mol
  3. -1.00 ´ 103 kJ/mol
  4. 1.00 ´ 103 kJ/mol
  5. 2.14 ´ 103 kJ/mol

32. Consider the following system at equilibrium:

H2(g) + I2(s) + 68.0 kJ/mol 2HI(g)

Which of the following will shift the equilibrium to the right?

  1. increasing the temperature
  2. decreasing the temperature
  3. increasing the volume
  4. decreasing the volume
  5. removing some HI(g)
  6. adding some HI(g)
  7. removing some I2(s)
  8. adding some I2(s)
  1. 1, 3, 5
  2. 2, 6, 7
  3. 1, 5, 8
  4. 1, 3, 5, 8
  5. 2, 4, 6, 7

33. On the weak acid/strong base titration curve shown, identify the equivalence point and a point corresponding to a buffer.

equivalence point buffer

  1. c a
  2. d b
  3. b e
  4. b f
  5. d f

34. Calcium carbonate reacts with hydrochloric acid to produce which gas?

  1. H2
  2. O2
  3. Cl2
  4. CO
  5. CO2

35. List, in order (i) through (iv), the functional group for each of the following compounds:

(1) alcohol

(2) aldehyde

(3) amide

(4) carboxylic acid

(5) ester

(6) ether

(7) ketone

A. 2,1,3,7

B. 7,2,3,6

C. 7,1,4,2

D. 5,6,4,2

E. 3,1,5,2

36. Which of the following fundamental particles has the largest mass?

A. beta

B. gamma

C. proton

D. neutron

E. alpha

CHE 116 XXX Spring 2007 Final Exam