Chemistry
Raymond Chang
10th edition
Chapter 14
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Question 1
The reaction N2O4(g) ↔ 2NO2(g) is
endothermic. Which of the following is true?
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A) Decreasing the pressure
drives the reaction to the right.
B) Increasing the
temperature drives the reaction to
the right.
C) Decreasing the volume
drives the reaction to the left.
D) All of the above.
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Question 2
If an equilibrium for a reaction is said to lie
to the right then the equilibrium constant
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A) is a negative value.
B) is a positive value
less than one.
C) is a positive value
greater than one.
D) is equal to one.
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Question 3
The value of the equilibrium constant is not
affected by the concentrations of
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A) pure solids and liquids.
B) gases.
C) aqueous solutions.
D) all of the above.
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Question 4
The value of an equilibrium constant
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depends on
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A) the rate of the reaction.
B) how the equilibrium
equation is balanced.
C) the starting
concentrations of the reactants.
D) all of the above.
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Question 5
For a particular set of concentrations, if the value of
Q is much greater than the value of the equilibrium
constant, K, for a reaction, then
A) the initial rate of the reaction will be
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very fast, but will slow as equilibrium is
approached.
B) the reaction will proceed to the right,
but the rate cannot be determined from the Q or
K.
C) the reaction will proceed to the left, but
the rate cannot be determined from the Q or K.
D) the reaction will proceed to make more
products if the value of K is much greater than
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one.
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Question 6
Consider the reaction of hydrogen gas and
oxygen gas to produce liquid water. Which
of the following is true?
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A) The position of the equilibrium is
unaffected by the addition of liquid water.
B) Removing some of the hydrogen gas
has no effect on the position of the
equilibrium.
C) Reducing the volume of the reaction
vessel has no effect on the position of the
equilibrium.
D) None of the above are true.
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Question 7
Which of the following is (are) unaffected
by reversing the direction in which a
chemical equation is written?
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A) The equilibrium concentrations
B) The equilibrium constant value
C) The mass action expression
D) All of the above
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Question 8
The reaction of oxygen with hemoglobin
produces oxyhemoglobin, which carries
oxygen to body tissues. At high altitudes the
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following results are seen
A) the lower oxygen pressure causes the
equilibrium to shift away from
oxyhemoglobin.
B) “altitude sickness" can occur in
unacclimated individuals.
C) people who live in higher altitudes
develop higher levels of hemoglobin to
function normally.
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Question 9
The reaction of hydrogen gas with
nitrogen gas to produce ammonia gas is
exothermic. Which of the following is
true?
A) Increasing the pressure of the reaction
system will increase production of ammonia.
B) Condensing the ammonia gas
produced into liquid will increase the
production of ammonia.
C) Decreasing the temperature of the
reaction will increase the production of
ammonia.
D) All of the above.
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Question 10
If a reaction is endothermic, then the
equilibrium constant is higher at higher
temperature.
A) True
B) False
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Question 11
Consider the chemical change AB. After
the reaction starts, but before the system
reaches equilibrium, the only process that
takes places is A being converted into B.
A) True
B) False
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Question 12
Chemical reactions take place because the
molecules involved in a reaction
A) break apart spontaneously, then
recombine.
B) exist only above a certain
temperature.
C) collide with each other and
break bonds.
D) are moving very fast.
E) are very unstable.
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Question 13
Which of the following statements is true of
a catalyst?
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A) Its concentration stays
constant throughout the reaction
B) it increases the rate of a
reaction
C) it provides a new pathway
for the reaction
D) all of the above
E) none of the above
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Question 14
For reactions in gas phase, a relationship can be
established between Kc and Kp. For which of the
following processes will the two constants have the
same numerical value?
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A) formation of water vapor from
hydrogen and oxygen
B) formation of carbon dioxide from
carbon monoxide and oxygen
C) synthesis of ammonia from
hydrogen and nitrogen
D) decomposition of hydrogen iodide
into hydrogen and iodine gas
E) conversion of nitrogen dioxide into
dinitrogen tetroxide
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Question 15
Calculate the equilibrium constant for
the process AB, given the following
equilibrium concentrations:
[N2O4] = 0.0427 M ; [NO2] = 0.0141 M
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A) 6.60x10-1
B) 215
C) 0.00466
D) 0.330
E) 3.03
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Question 16
Consider the following reaction:
4HCl(g) + O2(g) ↔ 2H2O(g) + 2Cl2(g)
with DH = -114.4 kJ
One way to decrease the amount of
chlorine present at equilibrium is
A) removing the water vapor while it is
being formed.
B) raising the temperature.
C) adding more hydrogen chloride.
D) decreasing the volume of the
reaction vessel.
E)
none of the above.
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Question 17
The concentrations of pure solids are normally
excluded in an equilibrium constant expression
because
A) these substances do not participate in
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the processes that are at equilibrium.
B) at the time the equilibrium is
established, their absolute amounts have
not varied from the original amounts.
C) the concentration of a pure solid
remains essentially constant throughout
the reaction.
D) they do not play a vital role in the ratedetermining step of the reaction.
E)
none of the above.
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Question 18
At equilibrium
A) the rate constants for
the forward and reverse
reactions are equal.
B) the reaction ends.
C) all reactants have
been converted to products.
D) the forward and
reverse rates are equal.
E) none of the above.
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Question 19
Consider the following reaction:
CaCO3(s) ↔ CO2(g) + CaO(s) . What will
happen to the system if more CaCO3 is
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added?
A) nothing
B) the amount of CaCO3 will
decrease
C) less CaO will be produced
D) the pressure will increase
E) the concentration of CO2 will
decrease
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Question 20
Consider the following reaction:
2H2(g) + 2Cl2(g) ↔ 2HCl(g) + heat . What
will happen to the system if the volume
of the reaction vessel is decreased?
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A) more HCl will dissociate
B) amounts of H2 and Cl2 will
decrease
C) less heat is produced
D) all of the above
E) none of the above
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Answer Key – Chapter 14
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
D
C
A
B
C
A
A
D
D
A
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
B
C
D
D
C
B
C
D
A
B