Deck 8: Energy From Electron Transfer

Question 1

Which type of widely used battery is not rechargeable?

A)zinc-manganese alkaline
B)lithium-ion
C)lead-acid (storage batteries)
D)nickel-cadmium (NiCad)

Answer 1

zinc-manganese alkaline

Question 2

Compare commercial electrical power plants,batteries,and solar cells in terms of their efficiencies in producing electrical energy.Rank them from least efficient to most efficient.

A)solar cells,batteries,electrical power plants
B)electrical power plants,solar cells,batteries
C)batteries,solar cells,electrical power plants
D)solar cells,electrical power plants,batteries

Answer 2

solar cells,electrical power plants,batteries

Question 3

Which type of battery is best for use in heart (cardiac)pacemakers?

A)alkaline
B)lithium-iodine
C)mercury
D)nickel-cadmium

Answer 3

lithium-iodine

Question 4

Which is an oxidation half-reaction?

A)2 H₂ + O₂ → 2 H₂O
B)Zn → Zn²⁺ + 2 e¯
C)2 HCl + Ba(OH)₂ → 2 H₂O + BaCl₂
D)Cl₂ + 2 e¯ → 2 Cl¯

Question 5

Which type of battery is widely used to store the excess energy generated by windmill farms and solar panels?

A)alkaline
B)lithium ion
C)lead acid
D)nickel-metal hydride

Question 6

What condition must be met for a battery to be rechargeable?

A)Either its anode or its cathode must generate a gas as a result of the electrochemical reaction.
B)It must generate electricity via an acid-base reaction rather than via an oxidation-reduction reaction.
C)The battery must be open to the outside so that it can vent any internal pressure that builds up from gases within it.
D)The electrochemical reaction of the battery must be reversible.

Question 7

In an electrochemical cell,the anode is

A)the electrode at which oxidation takes place.
B)the material used to connect the two half cells to each other.
C)always used up before the cathode.
D)never a metal.

Question 8

Chemical energy is converted directly into electrical energy in

A)a battery.
B)an electrical power plant.
C)an electrolytic cell.
D)an automobile's engine.

Question 9

Why can the lead-acid batteries used in cars generate electricity for several years before running down?

A)A lead-acid battery is so large that it holds large quantities of the chemicals whose electrochemical interaction creates the electricity.
B)The mechanical motion of the engine drives an alternator that generates electricity to recharge the battery.
C)These batteries are used only to generate the electricity that makes the first spark plug "spark." Therefore,they are hardly used at all when a car is started,and never when it is driven.
D)The electrons they generate,not the chemical components,provide almost all of the electricity.

Question 10

Very small mercury batteries have been made and used in a multitude of applications.Why have they been replaced by other kinds of batteries for most applications?

A)Mercury has become far too expensive to use in batteries.
B)Mercury is poisonous and difficult to dispose of.
C)These batteries cannot generate enough current for any modern devices.
D)Though they may be made very small,they are far too heavy to use in most applications.

Question 11

Which is the cathode in this galvanic cell?

A)the solid zinc electrode
B)the Zn²⁺(aq)ions in the 1 M solution
C)the solid silver electrode
D)the Ag⁺(aq)ions in the 1 M solution

Question 12

What is the primary determinant of the voltage developed by a battery?

A)the nature of the materials in the reaction
B)the age of the battery
C)the overall size of the galvanic cells
D)the size of the electrodes

Question 13

In a fuel cell,

A)there is oxidation,but no reduction.
B)reduction takes place at the cathode.
C)there is direct conversion of mechanical energy into electricity.
D)a chemical reaction produces heat,which then produces electricity.

Question 14

Whenever a substance is oxidized,

A)it is called the oxidizing agent.
B)some other substance must be reduced.
C)it gains electrons.
D)hydronium ions are produceD.

Question 15

Which is not a necessary consideration for a battery designed to run a cell phone or portable MP3 player?

A)It must develop a useful level of electrochemical potential.
B)It must "run" for a reasonable amount of time.
C)It must use liquid,aqueous solutions.
D)It must be fairly light in weight.

Question 16

In a voltaic cell,

A)oxidation takes place at the cathode.
B)reduction takes place at the anode.
C)oxidation and reduction take place at the same time at the anode and cathode respectively.
D)electrical energy is used to reverse spontaneous chemical reactions.

Question 17

The current through a wire is most closely related to the

A)energy of the electrons flowing through the wire.
B)type of electrons flowing through the wire.
C)charge of some number of electrons flowing through the wire.
D)oxidation potential of the electrons flowing through the wire.

Question 18

During the chemical reaction in an electrochemical cell,

A)a substance is oxidized and gains electrons.
B)electrons travel from the cathode to the anode.
C)oxidation takes place alone,without an accompanying reduction.
D)oxidation occurs at the anode.

Question 19

In this electrochemical cell,the reduction half reaction is

A)Cu²⁺(aq)+ 2 e¯ → Cu(s)
B)Zn(s)→ Zn²⁺(aq)+ 2 e¯
C)Zn(s)→ Cu(s)
D)Cu²⁺(aq)→ Zn²⁺(aq)

Question 20

The opposite of a galvanic cell is

A)a battery.
B)an electrolytic cell.
C)a fuel cell.
D)a photovoltaic (solar)cell.

Question 21

Which is not a current or planned use for the electricity generated by fuel cells?

A)as the output of small power plants
B)to operate space shuttles
C)to control nuclear fusion
D)to power a cell phone

Question 22

The Prius,a hybrid car produced by Toyota,uses a battery that its maker claims should not have to be recharged or replaced during the lifetime of the car.The type of battery used in the Prius is

A)alkaline.
B)lead acid.
C)nickel-cadmium.
D)nickel-metal hydride.

Question 23

In general,a modern hybrid vehicle is less polluting than a standard vehicle because it runs on both a

A)gasoline engine and an electric motor run by a rechargeable battery.
B)gasoline engine and a fuel cell.
C)fuel cell and an electric motor run by a rechargeable battery.
D)gasoline engine and a cleaner diesel engine.

Question 24

Sunlight (solar radiation)may be turned directly into electricity using ______ cells.

A)fuel
B)photovoltaic
C)electrolytic
D)lead-acid

Question 25

Which is not an advantage of using a solid electrolyte in a fuel cell?

A)It is impermeable to liquids and gases and will keep the fuel and oxidizer separated.
B)It cannot "dry out" and will allow the fuel cell to operate at higher temperatures than one that uses water as part of the proton transfer mechanism.
C)It may use various fuels other than hydrogen gas,the fuel of choice in systems using water as part of the proton transfer mechanism.
D)It eliminates the need for an oxidant;only a fuel is requireD.

Question 26

A major advantage of a fuel cell over a standard battery is that

A)as long as oxygen and fuel are supplied,a fuel cell will not "run down" like a battery will.
B)a fuel cell generates electricity without the need for an oxidation-reduction reaction.
C)a fuel cell is 100% efficient at generating electricity,whereas a battery is less than 1% efficient.
D)as it generates electricity,a fuel cell produces more fuel than it uses.

Question 27

To date,solar radiation is not a practical source for the production of electricity used to power

A)electric highway signs.
B)security lighting in parking lots.
C)satellites in orbit around the earth.
D)fleets of taxis.

Question 28

The "doping" of a semiconductor to improve its performance means

A)slightly raising the temperature of a pure semiconductor to improve the ability of its electrons to flow from atom to atom.
B)fusing layers of two different pure semiconductors together to give the electrons that absorb the solar radiation characteristics of the electrons of both semiconductors.
C)mixing large amounts of a metal with small amounts of a semiconductor so that the metal itself becomes a semiconductor.
D)adding small amounts of other elements to the pure semiconductor to change the freedom of electron motion throughout the crystal.

Question 29

What is the purpose of the hot KOH solution in the fuel cell?

A)It is the product of the reaction between the hydrogen,the oxygen,and the electrodes.
B)It keeps the electrodes conditioned and ready to work at high efficiency.
C)It is part of the acid-base reaction that generates the electricity in most fuel cells.
D)It maintains electroneutrality by working as an electrolyte;allowing transfer of ions between the half cells where the hydrogen and oxygen react.

Question 30

For safety and other practical reasons,the most logical use for hydrogen as a fuel in the near future is

A)in an electric power plant.
B)in a fuel cell.
C)for running an automobile.
D)for nuclear fusion.

Question 31

Which is not a component of a fuel cell?

A)a timer
B)an anode
C)a cathode
D)an electrolyte

Question 32

What moves in the salt bridge from the cathode to the anode?

A)electrons
B)Zn⁺² ions
C)Cu⁺² ions
D)anions

Question 33

Semiconductors,such as the element silicon,may be used in cells that convert solar radiation to electricity.One of the major difficulties encountered in using silicon is that it

A)is one of the rarest of all elements and therefore difficult to find on earth.
B)is expensive to produce large quantities of extremely pure silicon.
C)quickly evaporates when isolated in a pure state.
D)is the most active of all the elements,so it cannot be prepared in a pure state.

Question 34

How does using hydrogen as the fuel in an electric power plant compare with using hydrogen as the fuel in a fuel cell?

A)H₂ used as a fuel in a power plant must be more pure than the H₂ used in a fuel cell.
B)Burning H₂ in a power plant produces many more pollutants than using H₂ in a fuel cell.
C)A fuel cell using hydrogen operates at a higher overall efficiency than would a power plant burning hydrogen as a fuel.
D)Using H₂ in a fuel cell generates far more heat than burning it in a power plant.

Question 35

Which has not been suggested as a reasonably practical way to store large amounts of hydrogen in relatively small spaces for its use as a fuel?

A)Liquefy hydrogen under pressure and store it much as we do with liquefied natural gas today.
B)Absorb hydrogen onto activated charcoal;then heat the mixture to release the hydrogen.
C)Store it in the form of ionic metal hydrides,such as LiH,which release hydrogen gas when they react with water.
D)Encapsulate hydrogen molecules in fullerene molecules (large,carbon-based molecules that can act like cages)that may be heated later to release the hydrogen.

Question 36

A fuel cell does not "run down" like a standard battery because

A)the reactants in a battery must be stored inside the battery,whereas the reactants for a fuel cell flow in as needed.
B)a fuel cell continually recycles the same electrons,whereas a battery must continually generate new ones.
C)a battery is completely dependent upon oxidation-reduction reactions,whereas a fuel cell depends on acid-base reactions.
D)a battery has many moving parts,whereas a fuel cell has none.

Question 37

Semiconductors are more effective than metals as converters of solar radiation into electricity because

A)it is easier for the atoms of a semiconductor to absorb solar energy and to move from place to place within the solid,thereby conducting electricity.
B)the energy contained in sunlight gives the valence electrons in the semiconductor atoms the extra energy they need to "flow" throughout the solid.
C)metals melt much too easily under direct sunlight and,as liquids,lose their ability to conduct electricity.
D)solar radiation has sufficient energy to knock electrons completely off the metal surface,making it impossible for the electrons to "flow" from atom to atom and conduct electricity.

Question 38

At present,it will be difficult and perhaps inappropriate to develop an economy based on burning hydrogen rather than natural gas or gasoline because

A)hydrogen is a dirty fuel.Burning hydrogen produces significantly more pollutants than burning natural gas or gasoline.
B)hydrogen is not an efficient fuel.Per gram,hydrogen has about the lowest heat of combustion of any known substance,much lower than natural gas or gasoline.
C)although hydrogen is abundant,pure hydrogen is not found naturally on earth.Hydrogen is difficult or expensive to isolate and collect.
D)being such a light element,hydrogen will not flow through pipelines the way natural gas or gasoline do.Hydrogen cannot easily be delivered from where it is produced to the places where it is needeD.

Question 39

How does the reaction of hydrogen and oxygen to produce energy in a fuel cell differ from their interaction during the direct combustion of hydrogen and oxygen?
I.The direct combustion of hydrogen and oxygen produces several different products,whereas the fuel cell produces only water.
II.Much less heat energy is produced in a fuel cell than via direct combustion of hydrogen and oxygen.
III.In the fuel cell,there is an oxidation-reduction reaction between hydrogen and oxygen.In the direct combustion of hydrogen and oxygen,there is no such reaction.
IV.It is much easier to control the hydrogen and oxygen during direct combustion than during their reaction in a fuel cell.

A)I and II only
B)I,II and III only
C)I,II,III and IV
D)I and III only

Question 40

As fuel cells become more widely accepted and are used more,we will

A)become less dependent on electrical energy.
B)become more dependent on fossil fuels and less dependent on renewable resources for power generation.
C)be able to generate electricity in places where we cannot now do so.
D)use coal as our primary energy source.

Question 41

Which of the following statements is not true about PEM fuel cells?

A)PEM fuel cells rely on inexpensive catalysts.
B)PEM fuels cells are cleaner than gasoline powered vehicles.
C)PEM fuel cells have safe and efficient fuel storage.
D)PEM fuel cells have limited driving range.

Question 42

Batteries must be used in addition to solar cells when generating household electricity because

A)solar cells can generate electricity only via the output of a battery.
B)solar cells can generate only a small fraction of the total energy needed by a household at any one time.
C)solar cells generate so much electricity that they will overheat if they cannot transfer the excess electricity somewhere to dissipate the extra heat.
D)batteries must supply the energy when sunlight is not available.

Question 43

Among the alternative sources for generating electricity are
I.batteries.
II.fuel cells.
III.solar cells.
In populated but remote regions where it has proven too expensive or too difficult to establish electrical networks,which is/are the most viable alternative method(s)of providing electricity?

A)I only
B)I and II only
C)II and III only
D)I and III only

Question 44

Which is not a valid argument supporting the continued use of fossil fuels?

A)We will still be using only a small fraction of the total usable surface of the earth if we open new,formerly protected areas to exploration.
B)We are continuing to find more efficient ways to use fossil fuels as energy resources.
C)We will recover more from a particular source than we were able to in the past as we improve the technologies by which we recover these fuels from the earth.
D)We are improving the technologies used to remove pollutants from our fossil fuels before we use them and from the materials produced after we use them.

Question 45

Electrolysis is a process that

A)produces an electrical current.
B)requires an electrical current.
C)produces heat energy.
D)requires heat energy.

Question 46

Silicon has 4 electrons in its outer energy level,gallium has 3.Adding small amounts of gallium to pure silicon

A)destroys the ability of the silicon to act as a semiconductor.
B)provides the basis for using the silicon as a fuel cell.
C)creates a p-type semiconductor.
D)creates an n-type semiconductor.

Question 47

The aluminum-air battery is being considered for use in automobiles.In this battery,aluminum metal undergoes oxidation to Al³⁺ ions and forms Al(OH)₃.O₂ from the air undergoes reduction to OH¯ ions.Which half-reaction occurs at the anode?

A)formation of OH¯ ions from O₂.
B)capturing O₂ from the air so that it may form the OH¯ ions.
C)formation of Al³⁺ ions from aluminum.
D)reaction of Al³⁺ ions with hydroxide ions to produce Al(OH)₃.

Question 48

Reforming processes can store hydrogen fuel in a liquid form as another molecule.Which of the following cannot be reformed into hydrogen?

A)methanol
B)gasoline
C)diesel
D)carbon dioxide

Question 49

A candle may be considered a more efficient producer of light than a flashlight because it

A)converts chemical energy directly into light.
B)produces more heat than a flashlight.
C)does not have a battery to recharge or replace.
D)may be used in remote locations far from electrical networks or power lines.

Question 50

Which argument(s)for the increasing use of solar energy is/are valid?
I.Solar cells are becoming cheaper and increasingly more efficient.
II.The cost of generating electricity from fossil fuels is increasing.
III.Limited and uncertain supply and the increasing requirements for pollution control are raising the cost of using fossil fuels.

A)I only
B)II only
C)I and III only
D)I,II and III

Question 51

A NiCd battery uses nickel and cadmium to produce a potential difference. Using these equations, answer the following questions.

Which equation represents what takes place at the anode?

A)I
B)II
C)III
D)I and II

Question 52

Why doesn't water naturally become hydrogen and oxygen gas when exposed to light?

A)Thermal energy is the only appropriate type of energy to split water.
B)You must use electrons to split water.
C)Water doesn't absorb the proper wavelength of light to split.

Question 53

In the lead-acid (storage)battery,
The cathode is the

A)H₂SO₄ electrolyte.
B)negative plates,lead/spongy lead.
C)positive plates,lead/PbO₂.
D)casing enclosing the entire battery.

Question 54

Which increases the efficiency of a photovoltaic or solar cell?
I.Replacing crystalline silicon with its non-crystalline form.
II.Increasing the number of alternating p- and n-type layers of semiconductors.
III.Decreasing the thickness of each alternating p- and n-type layer of semiconductor.

A)I and II only
B)II and III only
C)I and III only
D)I,II,and III

Question 55

A NiCd battery uses nickel and cadmium to produce a potential difference. Using these equations, answer the following questions.

Which equation best represents the reduction half-reaction?

A)I
B)II
C)III
D)I and II

Question 56

A NiCd battery uses nickel and cadmium to produce a potential difference. Using these equations, answer the following questions.

Which equation represents the whole chemical reaction within the galvanic cell?

A)I
B)II
C)III
D)I and II

Question 57

Which is not a valid argument supporting the switch from using fossil fuels to using solar cells to generate our electricity?

A)The conversion reduces environmental damage from the extraction and transport of fossil fuels.
B)The conversion will lower the level of air pollution from sulfur and nitrogen oxides.
C)The conversion can be done quickly,efficiently,and relatively inexpensively if we just put our minds and our will to it.
D)The conversion will reduce the potential for global warming as less carbon dioxide is produced in the generation of electricity.

Question 58

In this photovoltaic (solar)cell,
The n-type semiconductor is in the region labeled

A)A
B)B
C)C
D)D

Question 59

In a solar cell,placing semiconductors of the p-type and n-type in contact with each other via a conducting wire accomplishes these two things:

A)It ensures that the current flows in a specific direction as it facilitates the conduction of electricity.
B)It ensures that only certain energies of solar radiation cause electricity to flow as it facilitates the conduction of electricity.
C)It ensures that only certain energies of solar radiation cause electricity to flow as it facilitates the flow of electricity in either direction.
D)It ensures that only oxidation takes place as it facilitates the conduction of electricity.

Question 60

In recently designed fuel cells the corrosive acidic or alkaline electrolyte is replaced with

A)a solid polymer.
B)mercury.
C)lead.
D)pure water.

Question 61

What about the bonding of silicon makes it useful as a semiconductor but not as a conductor of electricity?

A)The electrons are transferred forming ions that conduct electricity.
B)The electrons are shared in covalent bonds between atoms.
C)The electrons form a "sea of electrons" that move between many atoms.
D)The electrons are somewhat shared and somewhat transferred because it is a metalloiD.

Question 62

Given this diagram,
This semiconductor is

A)made of pure silicon.
B)carrying an extra electron.
C)missing an electron.
D)excited by a photon.

Question 63

What metal is used to dope an n-type semiconductor?

A)arsenic
B)cadmium
C)gallium
D)silicon

Question 64

What sort of energy is associated with energy from wind?

A)Potential energy
B)Thermal energy
C)Kinetic energy
D)Chemical energy

Question 65

Which of these locations would be best suited to geothermal energy as a source to operate homes?

A)Hawaii
B)Oklahoma
C)Vermont
D)England

Question 66

What is a difference between solar energy from solar cells and solar energy from concentrating solar power (CSP)?

A)There is no difference.
B)Solar cells do electron transfer while CSP relies on heat energy.
C)Solar cells rely on temperature to operate.
D)CSP relies on doped semiconductors to do electrical work.

Question 67

How do the interactions that are broken in water when it is boiled compare with those broken when water is electrolyzed?

A)Boiling water breaks intermolecular attractions and electrolysis breaks covalent bonds.
B)Boiling water breaks covalent bonds and electrolysis breaks intermolecular attractions.
C)Boiling water and electrolysis of water break covalent bonds.
D)Boiling water and electrolysis of water break intermolecular forces.

Question 68

As of 2007,what is the maximum efficiency of a multijunction solar cell?

A)15%
B)80%
C)22%
D)40%

Question 69

How is wind energy related to the sun?

A)It has no relation.
B)Wind turbines need solar panels to operate correctly.
C)The heat of the sun drives large-scale movements of air.
D)Wind turbines only operate during daylight hours.

Question 70

Why is it so expensive to ship hydrogen as a liquid as is often done with other gas?

A)Hydrogen is very heavy to ship.
B)Hydrogen is very dense to ship.
C)Hydrogen has to be shipped at a very low temperature.
D)Hydrogen in very flammable.