Transcript Document

Clicker Questions
Chapters 13, 14, 15
Dana and Michelle Chatellier
University of Delaware
© 2012 Pearson Education, Inc.
The rule of “like dissolves like”
refers to similarities between
_______ of miscible liquids.
a.
b.
c.
d.
molecular weights
shapes
intermolecular attractive forces
densities
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Which of the following
compounds is miscible with
water?
a.
b.
c.
d.
CH3OH
CH4
C 6H 6
CH3CH2OCH2CH3
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Which of the compounds
below is the LEAST miscible
with water?
a.
b.
c.
d.
CH3OH
CH3CH2OH
CH3CH2CH2OH
CH3CH2CH2CH2OH
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_______ Law says that the
solubility of a gas in a liquid
increases as the pressure of
the gas increases.
a.
b.
c.
d.
Boyle’s
Charles’s
Henry’s
Raoult’s
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_______ Law says that the
vapor pressure of a solution is
proportional to the mole
fraction of the solvent.
a.
b.
c.
d.
Boyle’s
Charles’s
Henry’s
Raoult’s
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The molality of a solution is
defined as the amount of
solute (in moles) divided by
the
a.
b.
c.
d.
volume of the solution (in liters).
mass of the solvent (in kilograms).
mass of the solution (in kilograms).
total number of moles.
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In general, as the temperature
of a solution increases, the
solubility of a gaseous solute
a.
b.
c.
d.
increases.
decreases.
remains unchanged.
varies from gas to gas.
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What is the freezing point of a
2.00 m aqueous solution of
sucrose? The value of Kf for
water is 1.86 degrees C/molal.
a.
b.
c.
d.
–3.72 degrees C
–1.86 degrees C
+1.86 degrees C
+3.72 degrees C
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What is the vapor pressure of
a solution containing 0.500
mol of glucose and 5.000 mol
of water at 29 degrees C?
a.
b.
c.
d.
30.0 Torr
27.3 Torr
25.0 Torr
2.7 Torr
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A 0.100 molal solution of
which compound below will
have the lowest freezing
point?
a.
b.
c.
d.
NaCl
CaCl2
KI
LiNO3
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What is the molecular weight
of adrenaline if 0.64 grams of
adrenaline dissolved in 36.0 g
of CCl4 raises the boiling point
by 0.49 degrees Celsius?
a. 180 g/mole
c. 720 g/mole
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b. 360 g/mole
d. 1800 g/mole
Light scattering by colloidally
dispersed particles is an
example of the _______
effect.
a.
b.
c.
d.
Tyndall
Raoult
Hall
Meissner
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The rate of a reaction can be
increased by
a.
b.
c.
d.
increasing reactant concentrations.
increasing the temperature.
adding a suitable catalyst.
All of the above
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Over time, the rate of most
chemical reactions tends to
_______.
a.
b.
c.
d.
increase
decrease
remain constant
oscillate
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If tripling the concentration of
reactant A multiplies the rate
by a factor of nine, the reaction
is _______ order in A.
a.
b.
c.
d.
zeroth
first
second
third
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Reaction: A + B  C + D
Rate = k[A][B]
The overall order of this
reaction is
a.
b.
c.
d.
first.
second.
third.
fourth.
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Reaction: W + X  Y + Z
Rate = k[W]
The order of this reaction with
respect to X is
a.
b.
c.
d.
zeroth.
first.
second.
third.
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The time required for the
concentration of a reactant to
be reduced to half of its initial
value is called the
a.
b.
c.
d.
midpoint of the reaction.
equivalence point of the reaction.
half-rate of the reaction.
half-life of the reaction.
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If k is the rate constant of a
first-order reaction, the half-life
of the reaction is:
a.
b.
c.
d.
0.693/k
0.693k
k/2
2k
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The value of the rate constant
(k) for a first-order reaction is
0.010 sec–1. What is the halflife of this reaction?
a.
b.
c.
d.
10 seconds
69 seconds
100 seconds
690 seconds
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A + B  products, Rate = k[A],
k = 0.010 sec–1, Initial [A] =
.100 M, Final [A] = .00100 M
How long will this take?
a.
b.
c.
d.
69 seconds
138 seconds
460 seconds
690 seconds
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Rate = k[A]2, Initial [A] = 0.100 M,
k = 0.0214 M–1 sec–1
What is the half-life of this secondorder reaction?
a.
b.
c.
d.
69 seconds
138 seconds
460 seconds
690 seconds
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Rate = k[A]2, Initial [A] =
0.100 M, k = 0.0214 M–1 sec–1
After 1.00 hour, what is the
concentration of reactant A?
a.
b.
c.
d.
0.0500 M
0.0250 M
0.0189 M
0.0115 M
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The minimum energy that a
collision between molecules
must have for a reaction to
occur is called the
a.
b.
c.
d.
initial energy.
internal energy.
external energy.
energy of activation.
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At 298 K, k = 1.36  10–7 sec–1.
At 323 K, k = 2.72  10–6 sec–1.
The energy of activation for this
reaction is
a.
b.
c.
d.
100 kJ/mole.
310 kJ/mole.
690 kJ/mole.
1000 kJ/mole.
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The rate-determining step is
the _______ step in a reaction
mechanism.
a.
b.
c.
d.
first
last
fastest
slowest
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Adding a catalyst increases
the rate of a chemical reaction
because the presence of the
catalyst
a.
b.
c.
d.
increases molecular velocities.
increases molecular collisions.
decreases energy of activation.
All of the above
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At equilibrium, the rate of the
forward reaction is _______
the rate of the reverse
reaction.
a.
b.
c.
d.
equal to
slower than
faster than
the reverse of
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The reaction quotient Q is
usually represented by
a.
b.
c.
d.
[reactants] / [products].
[products] / [reactants].
[reactants]  [products].
[reactants] + [products].
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If the value of the equilibrium
constant is large, then
_______ will mostly be
present at equilibrium.
a.
b.
c.
d.
reactants
products
catalysts
shrapnel
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If the value of the equilibrium
constant is small, then
_______ will mostly be
present at equilibrium.
a.
b.
c.
d.
reactants
products
catalysts
shrapnel
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Q = the reaction quotient
K = the equilibrium constant
At equilibrium, which is true?
a.
b.
c.
d.
Q>K
Q<K
Q=K
Q2 = K
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Equilibrium constants typically
have units of
a.
b.
c.
d.
M.
M2.
M1–.
None of the above
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Reaction quotients for
heterogeneous equilibria do
not include concentrations of
a.
b.
c.
d.
pure liquids.
pure solids.
Both of the above
Neither of the above
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HA ⇋
+
[HA] = 1.65  10–2 M and
[H+] = [A–] = 5.44  10–4 M at
equilibrium. Kc = _______.
+
H
a.
b.
c.
d.
–
A
1.79  10–2
1.79  10–3
1.79  10–4
1.79  10–5
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KP = KC when
a. the reaction is at equilibrium.
b. the reaction is exothermic.
c. all of the gases present are at
the same pressure.
d. the number of moles of gas on
both sides of the balanced
equation is the same.
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CO2 + H2 ⇋ CO + H2O
If all species are gases and H2
is added, the concentration of
CO at equilibrium will
a.
b.
c.
d.
increase.
decrease.
remain unchanged.
disappear.
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CO2 + H2 ⇋ CO + H2O
If all species are gases and
H2O is added, the equilibrium
concentration of CO
a.
b.
c.
d.
will increase.
will decrease.
will remain unchanged.
will disappear.
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CO2 + H2 ⇋ CO + H2O
If all species are gases and
CO2 is removed, the [CO] at
equilibrium will
a.
b.
c.
d.
increase.
decrease.
remain unchanged.
disappear.
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CO2 + H2 ⇋ CO + H2O
Increasing the temperature of
this endothermic reaction will
_______ [CO] at equilibrium.
a.
b.
c.
d.
increase
decrease
not change
eradicate
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CO2 + H2 ⇋ CO + H2O
If all species are gases and
the container is compressed,
the amount of CO will
a.
b.
c.
d.
increase.
decrease.
remain unchanged.
vanish.
© 2012 Pearson Education, Inc.
CO2 + H2 ⇋ CO + H2O
Adding a catalyst to this
reaction will cause the [CO] at
equilibrium to
a.
b.
c.
d.
increase.
decrease.
remain unchanged.
cease to exist.
© 2012 Pearson Education, Inc.