Chemistry for Changing Times, 14e (Hill/McCreary)
Chapter 15 Energy
15.1 Multiple Choice Questions
1) The SI unit of energy is the
A) joule.
B) calorie.
C) gram.
D) watt.
2) Approximately what percentage of the total solar radiation that falls upon the earth is immediately
reflected back into space?
A) 15%
B) 30%
C) 45%
D) 70%
3) Approximately what percentage of solar radiation is used to power the water cycle?
A) 10%
B) 23%
C) 30%
D) 70%
4) The solar energy-absorbing molecules of plants that power photosynthesis are called
A) carbohydrates.
B) photovoltaics.
C) solarases.
D) chlorophylls.
5) When the overall equation for the photosynthesis process is written and balanced, how many
molecules of water are required to make one glucose molecule, C6H12O6?
A) 1
B) 3
C) 6
D) 12
6) A watt is
A) 1 s/joule.
B) 1 cal/s.
C) 1 joule/s.
D) 1 s/cal.
7) How many joules of energy will a stock tank heater rated at 400 watts use in a 48 hour period?
A) 400
B) 400 × 48 × 60
C) 400 × 3600
D) 400 × 48 × 3600
8) The thin film of air, water, and soil in which all life exists is only about 15 km thick and is called the
A) atmosphere.
B) stratosphere.
C) biosphere.
D) hemisphere.
9) All of the following examples are classified as potential energy EXCEPT
A) energy stored by position.
B) energy in nuclear particles.
C) energy of a moving object.
D) energy in chemical bonds.
10) Which of the following situations would be an example of kinetic energy?
A) a compressed spring
B) a nuclear explosion
C) a tank of gasoline
D) a batter waiting for the ball to be pitched
11) Which of the following is a product of photosynthesis?
A) CO2
B) H2O
C) H2S
D) O2
12) Burning 1.000 mol of methane in oxygen to form carbon dioxide and water produces 803 kJ of energy.
How much energy is produced when 4.000 mol of methane is burned?
A) 358.0 kJ
B) 1606 kJ
C) 1205 kJ
D) 3212 kJ
13) The decomposition of 2 mol of water to hydrogen and oxygen requires 137 kcal of energy. The
reaction of hydrogen and oxygen to form 2 mol of water
A) requires 137 kcal.
B) releases 137 kcal.
C) requires more than 137 kcal.
D) releases more than 137 kcal.
14) Burning one mole of propane according to the following reaction:
C3H8(g) + 5 O2(g) → 3 CO2 + 4 H2O
liberates 526 kcal of energy. If all of the coefficients are tripled, how much energy will be released?
A) 526 kcal
B) 1052 kcal
C) 1578 kcal
D) 175.3 kcal
15) According to kinetic-molecular theory, reactions occur more rapidly at higher temperatures because
A) molecules move faster at higher temperatures.
B) molecules collide more frequently at higher temperatures.
C) molecules have more energy at higher temperatures.
D) All of the above are true.
16) Which of the following is an endothermic process?
A) evaporation of water
B) burning of wood
C) explosion of dynamite
D) discharging of a battery
17) Which of the following will cause the rate of a chemical reaction to speed up?
A) raising the temperature
B) increasing the concentration of reactants
C) adding a catalyst
D) All of these will speed up the rate of a reaction.
18) The first law of thermodynamics is sometimes called the law of
A) conservation of mass.
B) conservation of energy.
C) creation of energy.
D) destruction of energy.
19) The statement “you can’t get something for nothing” is another way of expressing
A) the first law of thermodynamics.
B) the second law of thermodynamics.
C) Boyle’s law.
D) the third law of thermodynamics.
20) The ________ law of thermodynamics states that in a spontaneous process, energy is degraded from
more useful forms to less useful forms.
A) first
B) second
C) third
D) fourth
21) The fact that a heat pump requires energy to move heat from a colder object (the outside of a house) to
a hotter object (the inside of the house) is a real life observation of which thermodynamic law?
A) the first law
B) the second law
C) the third law
D) the fourth law
22) The fact that a refrigerator requires energy to move heat from a colder object (the inside of the
refrigerator) to a hotter object (the outside of the refrigerator) is a real life observation of which law of
thermodynamics?
A) first law
B) second law
C) third law
D) fourth law
23) ________ is the measure of the dispersal of energy in a system.
A) Entropy
B) Enthalpy
C) Heat
D) Calories
24) Which physical state has the lowest entropy?
A) solid
B) liquid
C) gas
D) All have the same entropy.
25) Which physical state has the greatest entropy?
A) solid
B) liquid
C) gas
D) All have the same entropy.
26) The second law of thermodynamics defines
A) entropy.
B) energy.
C) heat.
D) temperature.
27) Which of the following does NOT result in an increase in entropy?
A) Water boils.
B) A child scatters her toys.
C) A student cleans his dorm room.
D) A hose sprays water.
28) In any conversion of energy from one form to another, some of the energy ends up as
A) entropy.
B) heat.
C) electricity.
D) radioactivity.
29) The inevitable energy lost as heat in the generation of electrical energy in the most efficient fossil fuel
based power plant is a result of
A) the first law of thermodynamics.
B) the second law of thermodynamics.
C) a poor understanding of energy conversion.
D) designed inefficiencies to increase costs to the consumer.
30) The number of possible microstates will be highest for a
A) solid.
B) liquid.
C) gas.
D) All will have the same number of microstates.
31) Which of the following will have the greatest amount of entropy?
A) steam
B) ice
C) water
D) All have the same amount of entropy.
32) Perhaps the first mechanical device used to convert energy into a more useful form was the
A) steam engine.
B) waterwheel.
C) windmill.
D) nuclear reactor.
33) The first fuel was
A) coal.
B) petroleum.
C) blubber.
D) wood.
34) Fuels are ________ forms of matter.
A) oxidized
B) reduced
C) acidic
D) basic
35) Which of the following is NOT a fossil fuel?
A) coal
B) natural gas
C) petroleum
D) wood
36) Which one of the following is a nonfuel?
A) H2
B) CCl4
C) CH4
D) C8H18
37) ________ were introduced into western Europe in the Middle Ages.
A) Waterwheels
B) Windmills
C) Automobile engines
D) Solar panels
38) Which of the following is a fuel?
A) HCl
B) H2O
C) C
D) CO2
39) Wood, crop residues, and ________ still remain the main sources of heat for one-third of the world‘s
people.
A) coal.
B) natural gas
C) petroleum
D) dried dung
40) Approximately what percentage of the energy used to support our current lifestyle comes from fossil
fuels?
A) 50%
B) 35%
C) 15%
D) over 85%
41) A substance that burns readily and releases significant amounts of energy is a(n)
A) reducing agent.
B) fuel.
C) endotherm.
D) catalyst.
42) The most abundant fossil fuel in the United States is
A) coal.
B) natural gas.
C) petroleum.
D) wood.
43) The United States is estimated to have approximately what percentage of the world’s coal reserves?
A) 10%
B) 25%
C) 40%
D) 80%
44) The primary element in coal is
A) carbon.
B) silicon.
C) oxygen.
D) chlorine.
45) The highest grade of coal is
A) anthracite.
B) bituminous.
C) lignite.
D) peat.
46) The lowest grade of coal is
A) anthracite.
B) bituminous.
C) lignite.
D) peat.
47) Given the following analysis of coal samples, which is the best fuel?
A) 95% C, 5% O
B) 75% C, 25% O
C) 50% C, 50% O
D) 25% C, 75% O
48) Most of the coal that exists today was formed ________ years ago.
A) 100
B) 1000
C) 1 million
D) over 300 million
49) A major inconvenience of coal as a fuel is that it is a(n)
A) solid.
B) liquid.
C) gas.
D) mixture of all three states.
50) Approximately what percentage of U.S. electricity is generated by the burning of coal?
A) 25%
B) 35%
C) 45%
D) 65%
51) When coal is burned, mineral impurities are converted to
A) sulfur dioxide gas that goes up the smokestack.
B) carbon dioxide and water.
C) metal oxide solids that remain behind as ash.
D) All of the above are products of burning coal.
52) When coal containing sulfur is burned, the sulfur is converted to
A) gaseous sulfur oxides that go up the smokestack.
B) liquid sulfur oxides that stay behind as ash.
C) solid sulfur oxides that stay behind as ash.
D) Sulfur is converted to all of the above.
53) When coal burns,
A) chemical energy is converted to heat energy.
B) heat energy is created.
C) chemical energy is destroyed.
D) heat energy is converted to electrical energy.
54) When coal is heated in the absence of air, the solid left behind is called
A) coal.
B) coke.
C) coal tar.
D) carbon.
55) When coal is heated in the absence of air, the condensed vapor collected during the heating is called
A) coal.
B) coke.
C) coal tar.
D) carbon.
56) Which of the following is NOT a disadvantage of using coal as a fuel source?
A) SO2 is released and contributes to air pollution.
B) Coal is the least abundant of the fossil fuels.
C) Strip mining is devastating to the environment.
D) The cost of transporting coal to power plants or factories is high.
57) Coal can be cleaned before it is burned. The flotation method separates coal from its major impurities
by taking advantage of the difference in ________ of these materials.
A) acidity
B) combustion
C) density
D) volatility
58) Which of the following did NOT contribute significantly to the conversion of plant material to coal?
A) There was sufficient oxygen for the cellulose in the plant materials to decay completely.
B) The plant material was buried under mud and water, separating it from the atmosphere.
C) The plant material was subjected to significant pressure.
D) The plant material broke down and small molecules containing a lot of hydrogen and oxygen were
given off.
59) The structural material of plants is largely
A) amylopectin.
B) coal.
C) amylose.
D) cellulose.
60) The major component of natural gas is
A) ethane.
B) methane.
C) butane.
D) octane.
61) An advantage of natural gas as a fuel is that it is
A) more abundant than coal.
B) easy to locate and extract.
C) the cleanest of the fossil fuels.
D) the product is carbon and water.
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62) When natural gas is burned in insufficient air, ________ can be (a) major product(s).
A) water
B) carbon and soot
C) methane
D) octane
63) Natural gas burns with a relatively clean flame. Which of the following potential pollutants is
produced in significant quantities during the combustion of natural gas in air?
A) sulfur oxides
B) nitrogen oxides
C) metal oxides
D) All of the above are produced in significant quantities.
64) Petroleum is best described as a
A) pure substance.
B) compound.
C) simple mixture.
D) complex mixture.
65) The main components of petroleum are
A) hydrocarbons.
B) carbohydrates.
C) fats and oils.
D) ionic compounds.
66) Recent evidence indicates that petroleum is derived from
A) plants.
B) microscopic land animals.
C) microscopic marine animals.
D) decomposition of volcanic ash.
67) To make crude petroleum more useful, it must be
A) distilled.
B) filtered.
C) reduced.
D) washed with water.
68) The fraction from the distillation of crude petroleum that is slightly heavier than gasoline is called
A) kerosene.
B) heating oil.
C) lubricating oil.
D) asphalt.
69) The yield of gasoline from crude petroleum can be increased by
A) catalytic cracking of lighter fractions.
B) catalytic cracking of heavier fractions.
C) simple distillation.
D) vacuum distillation.
70) Gasoline is a
A) compound.
B) pure substance.
C) simple mixture of C5 – C12 hydrocarbons.
D) complex mixture of C5 – C12 hydrocarbons.
71) A gasoline with an octane rating of 90 would give the same performance in a standard test engine as a
mixture of
A) 90% isooctane and 10% heptane.
B) 90% heptane and 10% isooctane.
C) 90 parts isooctane and 90 parts heptane.
D) 90 parts isooctane and 90 parts water.
72) Pure isooctane would have an octane rating of
A) 0.
B) 50.
C) 75.
D) 100.
73) Pure heptane would have an octane rating of
A) 0.
B) 50.
C) 75.
D) 100.
74) In general, a higher proportion of branched chain hydrocarbons in a gasoline formulation
A) increases octane rating.
B) decreases octane rating.
C) burns cleaner.
D) burns cooler.
75) What metal, when added as a compound, increases octane rating of gasoline?
A) Pb
B) Na
C) Ag
D) Au
76) Catalytic reforming is a process for converting
A) low octane rated alkanes into high octane rated aromatics.
B) high octane rated alkanes into low octane rated aromatics.
C) low octane rated alkanes into high octane rated branched alkanes.
D) high octane rated alkanes into low octane rated branched alkanes.
77) A compound that replaced tetraethyllead as an octane booster is
A) benzene.
B) heptane.
C) isooctane.
D) methyl tert-butyl ether.
78) Which substance is most effective in raising the octane rating of gasoline?
A) benzene
B) ethanol
C) methyl tert-butyl ether
D) tetraethyllead
79) The heating of large hydrocarbon compounds with a catalyst in the absence of oxygen is called
A) cracking.
B) catalysis.
C) reforming.
D) flocculation.
80) Which of the following petroleum fractions has the highest boiling point?
A) fuel oil
B) gasoline
C) heating oil
D) lubricants
81) The major components of petroleum is/are
A) benzene.
B) water.
C) organic compounds of sulfur.
D) hydrocarbons.