Chemistry 12 Exam Jan 2005 vT

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CHEMISTRY- SCH4U - FINAL EXAM
Length: 2 hours Teacher: Mr. Smiley
Total Marks: 100 Student Name:
Instructions:
1. This examination has 7 pages and is divided into 3 parts
2. Initial here_________ to indicate that all 7 pages have been received
3. Pages are double sided make sure that you answer all parts
4. Calculators may be used but not shared
5. A periodic table, Activity series reference, Solubility guidelines, Equilibrium
constants and answer sheet are also provided separate to this exam.
6. Follow all instructions given for each part

Part A: Multiple Choice (51 marks)

Identify the letter of the choice that best completes the statement or answers the
question. When finished Part A, transfer answers to the Answer sheet provided.

____ 1. An amine is characterized by what functional group?
a. -CO2CH3 d. -CHO
b. -NH2 e. -CONH2
c. -CO2H
____ 2. When two alcohols undergo a self condensation, what is formed?
a. liquid alcohol d. an aldehyde
b. a ketone e. an ether
c. an ester
____ 3. Which of the following is a secondary alcohol?
a. d. CH3OH

b. e. CH3CH2OH

c.
____ 4.

The correct name for compound above is which of the following?
a. chloropropylbenzene c. 1-chloro-3-phenyl-3-propene
b. 3-phenyl-1-choloropropyne d. 3-chloro-1-phenyl-1-propene
____ 5. The formula for methyl ethanoate is which of the following?
a. c.

b. d.

____ 6. Markonikov’s Rule states that when an alkene or alkyne reacts with either a hydrohalide or
with water that:
a. the carbon that already had the d. the carbon that has the fewest H
most H atoms receives the H atom atoms receives the H atom
b. the H atoms are lost as H2 gas e. the H atoms combine with O to
form water
c. Markonikov’s Rule does not apply
to this situation
____ 7. Which type of reaction will an alkene not undergo?
a. Addition d. dehydration
b. Polymerization e. hydration
c. Oxidation
____ 8. Which of the following classes of organic compounds does not contain oxygen?
a. Aldehydes d. ethers
b. Amines e. amides
c. amino acids
____ 9. The synthesis sequence shown here is best described as which of the following?

1. 2. 3.

a. (1) Dehydration; (2) halogenation; (3) hydrogenation
b. (1) Hydrogenation; (2) dehydration; (3) halogenation
c. (1) Hydrogenation; (2) halogenation; (3) dehydration
d. (1) Halogenation; (2) hydrogenation; (3) dehydration
e. (1) Dehydration; (2) hydrogenation; (3) halogenation
____ 10. Amines will not react with which of the following?
a. alkyl halides c. Ketones
b. carboxylic acids d. hydrogen chloride
____ 11. The 3p atomic orbital has the shape of
a. a sphere d. two perpendicular dumb-bells
b. a torus e. an egg
c. a dumb-bell
____ 12. Why do energy levels exist in atoms?
a. electrons are negatively charged
b. electrons are attracted to certain numbers of neutrons
c. electrons are able to possess any range of energy
d. electrons will only display certain colours
e. electrons are only able to possess quanta of energy
____ 13. "A region of space in which there is a high probability of finding an electron" is the definition of
a. orbital d. photon
b. absorption spectrum e. dipole
c. quantum
____ 14. Which of the following is the electron configuration for the valence shell of oxygen?
a. d.

b. e.

____ 15. Which of the following is the electron configuration for magnesium?
a. 1s22s22p8 d. 1s32s32p33s2
b. 1s32s32p43s2 e. 1s22s22p63s2
c. 1s22s22p73s1
____ 16. Which of the following is always true of all electrons in the same principal energy level.
a. they possess the same energy d. all of the above
b. they have opposite spins e. none of the above
c. they are in identical orbitals
____ 17. Which of the following are properties of alkali metals?
I. They have one valence electron.
II. They have high first ionization energies.
III. They are very reactive.
IV. Their most easily removed electron is in an s orbital.
a. I and II only d. III only
b. I and IV only e. I only
c. I, III and IV only
____ 18. According to VSEPR theory, molecules adjust their shapes to keep which of the following as far
apart as possible?
a. pairs of valence electrons d. mobile electrons
b. inner shell electrons e. lone pairs of electrons
c. bonding pairs of electrons
____ 19. Four pairs of electrons surrounding a central atom will be arranged
a. pyramidally d. linearly
b. spherically e. trigonally
c. tetrahedrally
____ 20. Which of the molecules, CO2, H2O, NH3, and BF3, will be polar?
a. CO2, NH3 and BF3 d. CO2, H2O and NH3
b. H2O and NH3 e. CO2 and BF3
c. H2O and BF3
____ 21. What would be the shape of a molecule containing a central atom attached to two other atoms
with one lone pair of electrons?
a. linear d. tetrahedral
b. bent e. trigonal bipyramidal
c. trigonal planar
____ 22. An exothermic reaction is one where
a. heat is transferred from the surroundings into a system
b. heat is transferred from a system into the surroundings
c. kinetic energy is transformed into potential energy
d. there is no transfer of heat
e. none of the above
____ 23. A chemical system in which matter cannot flow into or out of a system is described as
a. a closed system d. a chemical system
b. an open system e. none of the above
c. an isolated system
____ 24. In a calorimeter, a 1.0 g sample of magnesium is burned to form MgO. In doing so, 25.5 kJ of
energy are released. What is the Heat of Combustion in kJ/mol of magnesium?
a. 306.2 d. 25.5
b. 1.54 x 10 25 e. 620
c. 0.0392
____ 25. Which statement concerning the accompanying diagram is true?

a. His positive
b. system is endothermic
the
c. system releases heat to the surroundings
the
d. theheat content of the reactants is less than the heat content of the
products
e. the enthalpy of the products is greater than the enthalpy of reactants
____ 26. When a 'target' reaction can be expressed as the sum of other reactions, the heat of the 'target'
reaction is the sum of the enthalpy changes of the other reactions. This statement is referred to
as
a. Smiley’s Law d. Priestly's Law
b. Law of Conservation of Energy e. Boyle's Law
c. Hess's Law
____ 27. Given the following thermochemical data:
1. C2H2(g) + 5/2 O2(g)  2CO2(g) + H2O(l) H = –1.30 x 103 kJ
2. C2H6(g) + 7/2 O2(g)  2CO2(g) + 3H2O(l) H = –1.56 x 103 kJ
3. H2(g) + 1/2 O2(g)  H2O(l) H = –2.86 x 102 kJ

What is ΔH for the following reaction?
C2H2(g) + 2H2(g)  C2H6(g)

a. –2.60 x 101 kJ d. –5.46 x 103 kJ
b. –3.12 x 102 kJ e. 2.60 x 101 kJ
c. –5.72 x 102 kJ
____ 28. Consider the following equation for the combustion of hydrogen:
H2(g) + 1/2 O2(g)  H2O(g) + 243 kJ

In order to produce 1215 kJ of heat, how many grams of H2 must burn?
a. 12.0 g d. 0.250 g
b. 0.100 g e. 8.00 g
c. 10.0 g
____ 29. The following property can be measured to determine the rate of the reaction
a. change in mass
b. change in colour
c. change in volume
d. change in pressure
e. all of the above depending on the reaction
____ 30. In the reaction, N2(g) + O2(g)  2NO2(g) , if the concentration changes from 0.45 mol/L to 1.00
mol/L in 2 minutes, what is the overall rate of production of nitrogen dioxide in the system?
a. 3.64 mol/(L·min) d. 12.6 mol/(L·min)
b. 0.275 mol/(L·min) e. 0.333 mol/(L·min)
c. 0.137 mol/(L·min)
____ 31. The presence of a catalyst is thought to increase the rate of a reaction by
a. changing the products that are formed in the reaction
b. decreasing the enthalpy change of the reaction
c. increasing the enthalpy change of the reaction
d. decreasing the activation energy of the reaction
e. increasing the activation energy of the reaction
____ 32. If for the reaction , the rate law is determined to be , then
a. the order of the reaction is 0
b. increasing the concentration of Y will have no effect on the rate
c. increasing the concentration of X will have no effect on the rate
d. increasing the concentration of Y will increase the rate of the reaction
e. there is no way to determine the value of k
____ 33. If for the reaction , the rate law is determined to be , then
a. doubling the concentration of Y will double the rate of the reaction
b. halving the concentration of Y will double the rate of the reaction
c. doubling the concentration of X will double the rate of the reaction
d. halving the concentration of X will double the rate of the reaction
e. only changes to the concentration of Y will affect the rate of the reaction
____ 34. In the following diagram, the letter which represents the position of the activated complex is:

a. A d. D
b. B e. E
c. C
____ 35. If a reaction can be broken down into a reaction mechanism, then the steps of the reaction
mechanism are known as
a. stages of reaction d. elementary steps
b. activated complexes e. primary equations
c. reaction progress

____ 36. Consider the above reaction mechanism. The rate-determining step of this reaction is
a. elementary step 1
b. elementary step 2
c. elementary step 3
d. elementary steps 2 and 3
e. impossible to tell from this information
____ 37. Consider the above reaction mechanism. The reaction intermediates are formed in
a. elementary step 1
b. elementary step 2
c. elementary step 3
d. elementary steps 1 and 2
e. impossible to tell from this information
____ 38. Consider the above reaction mechanism. The rate-law equation from this reaction would be
a. d.

b. e. impossible to tell from this
information
c.

____ 39. 1.6 mol of CH3OH(g) are injected into a 4.0 L container and the following equilibrium becomes
established.
2H2(g) + CO(g) <=====> CH3OH(g) + 92 kJ
If at equilibrium 0.80 mol of CH3OH is still in the container the Ke must be which of the
following?
a. 0.78 d. 0.16
b. 25 e. 6.25
c. 5.0
____ 40. For the equilibrium system below, which of the following would result in a decrease in the
quantity of PCl5(g)?
PCl3(g) + Cl2(g) <=====> PCl5(g) + 45 kJ
a. increasing temperature d. decreasing the size of the container
b. adding some Cl2(g) e. injecting some He gas
c. decreasing temperature
____ 41. A concentrated weak acid is best described as which of the following?
a. a solution with a low pH
b. a solution where the concentration of undissociated acid particles is low
compared to the concentration of hydronium ions
c. a solution where the concentration of hydronium ions is large compared to
the concentration of undissociated acid particles
d. a solution with a high pH
e. a solution where the concentration of undissociated acid particles is high
and the relative quantity of hydronium ions is small
____ 42. The Ksp for a substance A2B is 1.2 x 10-12. The [B] must be which of the following?
a. 4.0 x 10-11 d. 1.3 x 10-4
b. 3.6 x 10-12 e. 2.6 x 10-4
c. 6.7 x 10-5
____ 43. In the reaction
+ + + +
Which of the following statements is correct?
a. is the reducing agent, and is the oxidizing agent
b.
is the reducing agent, and is the oxidizing agent
c.
is the reducing agent, and is the oxidizing agent
d. is the reducing agent, and is the oxidizing agent
e.
is the reducing agent, and is the oxidizing agent
____ 44. In the reaction
+ + + +
Which of the following statements is correct?
a.
hydrogen is oxidized and is the oxidizing agent
b.
hydrogen is oxidized and is the oxidizing agent
c.
carbon is oxidized and is the oxidizing agent
d.
manganese is oxidized and is the oxidizing agent
e.
carbon is oxidized and is the oxidizing agent
____ 45. Which of the following statements are true for the redox reaction:
+ + + +
I. the oxidation number of changes from +7 to +3
II. is the oxidizing agent

III. is oxidized to

IV. is the reducing agent
V. the oxidation number of changes from +1 to 0

a. II and IV d. IV and V
b. I and III e. III and V
c. II and III

____ 46. In the electrochemical cell above, the left half cell is set up with a zinc electrode in contact with
1.0 mol/L and the right half-cell is set up with a silver electrode in contact with 1.0
mol/L .

The relevant reduction potentials are

Which of the following statements is false?
a. the silver electrode is the cathode
b. the zinc electrode is the cathode
c. electrons in the external circuit will flow from zinc to silver
d. the standard cell potential for this cell is 1.56 V
e. the zinc electrode is the anode
____ 47. The following two half-reactions are involved in a galvanic cell:

At standard conditions, what species are produced at each electrode?
a. is produced at the cathode and at the anode
b.
is produced at the cathode and at the anode
c.
is produced at the anode and at the cathode
d.
is produced at the cathode and at the anode
e.
is produced at the cathode and at the anode
____ 48. Which of the following equations does not represent an oxidation-reduction reaction?
a. + +
b. + +
c. +
d. + +
e. +

____ 49. Experiments were performed with four strips of metals , , , and , and their corresponding
nitrate solutions , , , and . The following observations were
obtained:
A
no reaction no reaction no reaction no reaction

precipitate no reaction precipitate precipitate

precipitate no reaction no reaction no reaction

precipitate no reaction precipitate no reaction

Which of the following is the correct list of the metal ions in order of decreasing strength as
oxidizing agents (strongest oxidizing agent first)?
a. d.
b. e.
c.
____ 50. The function of the salt bridge in a galvanic cell is
a. to act as a nonelectrolyte
b. to provide an external circuit for the flow of electrons from one half-cell to
the other
c. to provide a path for the migration of ions from one half-cell to the other
d. to allow the solution in each half-cell to become electrically charged
e. to provide a path for the flow of electrons internally from one half-cell to the
other
____ 51. The oxidation number of chromium ( ) in the dichromate ion ( ) is
a. +2 d. +7
b. +4 e.
c. +6

Please answer the following on the paper provided.

Part B: Short Answer (10 marks)
1. Using Quantum Theory to explain give the stable ions that Zn and Pb can form. (4)
2. What would be the predicted shape of NO3-1 (Include the Lewis structure and VSEPR
diagram). Is this molecule polar or non-polar. Explain. (6)
3. Draw the structural formula and name the organic product for the following
reactions. Do not balance the equations. [6]

4. Give
Part C: Problems (18marks)

1. Balance the following redox reaction that takes place in a basic solution using the
half-reaction method: (5)
NO3-1 (aq) + Al (s)  NH3(aq) + Al(OH)4-1(aq)

2. Write the balanced chemical equation for the double displacement reaction of
calcium nitrate and sodium carbonate. [4]
3. Solve the ∆Hr for the following balanced equation using Hess’s Law and the given
data: [7]
C3H8 (g) + 5O2 (g)  3CO2 (g) + 4H2O (g)

C3H8(g)  3C(s) + 4H2(g) ∆H1 = +104 KJ
C(s) + O2(g)  CO2(g) ∆H2 = -393.5 KJ
H2O(l)  H2(g) + 1/2 O2(g) ∆H3 = +285.5 KJ

5. What is the pH of a 1.24 mol/L solution of HCN(aq) if its Ka = 6.2 x 10-10? (4)
Part D: Inquiry (28 marks)
1. A local candy company is developing a new apricot flavoured bubble gum. They have
offered you a one time consulting fee to develop an experimental design for the
production of pentyl butanoate, which is a synthetic ester that smells like apricot.
a) Your experimental design (summary of crucial materials and a overview of the
procedure), use any organic or inorganic compounds that you feel are useful. (5)
b) Give structural diagrams for all of the organic compounds and the reaction pathway
that you are using. (4)

2. Explain the following data regarding organic compounds in terms of intermolecular
forces involved in each compound. (7)
Compound Point (OC)
Ethane -89
Ethanal 21
Ethanol 78
Propanol 97

3. You are planning an investigation into the effects of various changes to a
chromate-dichromate equilibrium system in order to develop a yellow t-shirt dye. The
chromate ion (CrO42- (aq)) reacts with H+ to form the following equilibrium with the
dichromate ion (Cr2O72- (aq)) and H2O (l).

2CrO42- (aq) + 2H+(aq)  Cr2O72- (aq) + H2O (l)
{Yellow} {Orange}

Predict the direction of the equilibrium shift for the following changes; explain each prediction.
(6)

a) the addition of 0.1 M sodium hydroxide
b) the addition of 0.1 M hydrochloric acid
c) the addition of 0.1 M barium nitrate
4. Use the following data to calculate the reaction rate law and the rate law constant for the
system (6)

Experiment NO (mol/L) H2 (mol/L) Initial Rate of Reaction (mol/(L·s))

1 0.001 0.004 0.002

2 0.002 0.004 0.008

3 0.003 0.004 0.018

4 0.004 0.001 0.008

5 0.004 0.002 0.016

6 0.004 0.003 0.024
Answer Section

MODIFIED TRUE/FALSE

1. ANS: F, two

REF: I OBJ: 3.5 LOC: SP1.02
2. ANS: F, probable

REF: K/U OBJ: 3.7 LOC: SP1.02
3. ANS: F, very different

REF: I OBJ: 4.4 LOC: SP2.01
4. ANS: T REF: K/U OBJ: 5.1
LOC: EC2.02
5. ANS: F, elements only