Multiple Choice
Identify the
letter of the choice that best completes the statement or answers the question.
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1.
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Which
of the following types of energy is not kinetic energy? a. | thermal
energy | b. | electrical energy | c. | gravitational
energy | d. | mechanical energy | e. | sound
energy | | |
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2.
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Of
the following types of energy, which are potential energies?
1. thermal energy
2. chemical
potential energy
3. mechanical energy
4. electrostatic
energy
a. | 1
only | b. | 1 and
3 | c. | 2
only | d. | 2 and
4 | e. | 1, 2, and
4 | | |
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3.
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All
of the following statements are true EXCEPT a. | In an endothermic process heat is transferred from the
surroundings to the system. | b. | The greater the specific heat of an object, the more thermal
energy it can store. | c. | The SI unit of specific heat capacity is joules per gram per
kelvin. | d. | Heat is transferred from the system to the surroundings in an
exothermic process. | e. | The temperature of a system is a state
function. | | |
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4.
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How
much energy is required to change the temperature of 15.0 g Fe from 18.5ºC to 56.8ºC? The specific heat of iron is 0.451
J/g·K. a. | 57.5
J | b. | 127
J | c. | 259
J | d. | 385
J | e. | 452
J | | |
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5.
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If
25.0 g H2O at 11.2ºC is combined with 75.0 g H2O at 87.2ºC, what is the final temperature of the mixture? The specific heat of
water is 4.184 J/g·K. a. | 43.1ºC | b. | 68.2ºC | c. | 73.2ºC | d. | 74.4ºC | e. | 87.0ºC | | |
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6.
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75.0
g of ice at 0.00ºC is combined with 125 g water at 20.0ºC. The final temperature of the mixture is 0.00ºC. What mass of ice melts? (Heat of fusion = 333 J/g; specific heats:
ice = 2.09 J/g·K, water = 4.184 J/g·K) a. | 31.4 g | b. | 43.6
g | c. | 51.3
g | d. | 75.0
g | e. | 81.1
g | | |
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7.
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For a
particular process q = 25 kJ and w = -15 kJ. What conclusions may be drawn for this
process? a. | DE = 40
kJ | b. | DE = -40
kJ | c. | This is a
product favored reaction. | d. | Work is done by the system on the
surroundings. | e. | Both answer b and d are correct. | | |
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8.
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Which
of the following thermodynamic quantities are state functions: heat (q), work (w),
enthalpy change (DH), and internal energy change (DE)? a. | DH and DE | b. | DE only | c. | DE and w | d. | q and w | e. | DH and q | | |
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9.
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Determine the heat of reaction for the oxidation of iron,
4 Fe(s) + 3 O2(g) ® 2 Fe2O3(s)
given the enthalpies of the reactions
below.
2 Fe(s) + 6
H2O(ª) ® 2 Fe(OH)3(s) + 3
H2(g) | DH = 321.8 kJ | 2
H2(g) + O2(g) ® 2 H2O(ª) | DH = -571.7 kJ | Fe2O3(s) + 3 H2O(ª) ® 2
Fe(OH)3(s) | DH = 288.6 kJ | | |
a. | -1648.7
kJ | b. | -636.9
kJ | c. | -505.3
kJ | d. | 387.0
kJ | e. | +1447.1
kJ | | |
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10.
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Calculate the molar enthalpy of combustion of
C3H6(g),
C3H6(g) + 9/2 O2(g) ® 3
CO2(g) + 3 H2O(ª)
using standard
enthalpies of formation.
molecule | DHfº (kJ) | C3H6(g) | +53.3 | CO2(g) | -393.5 | H2O(ª) | -285.8 | | |
a. | -2091.2
kJ | b. | -1984.6
kJ | c. | -187.8
kJ | d. | -62.6
kJ | e. | +732.3
kJ | | |
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