Chapter 16 Study Questions Name:____________________________ Class:______________
Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.
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1. Which of the following is a use of radioactive material?
a. detecting smoke
c. generating electrical energy
b. locating defects in materials
d. all of the above
2. Which particle both begins and is produced by a nuclear chain reaction?
a. positron
c. alpha particle
b. neutron
d. beta particle
3. Nuclear radiation that can be stopped by paper is called
a. alpha particles.
c. gamma rays.
b. beta particles.
d. None of the above
4. The half-life of a radioactive atom is 2 months. If you start with 1 g of the element, how much will remain
after 6 months?
a. One-half of a gram will remain.
c. One-eighth of a gram will remain.
b. One-fourth of a gram will remain.
d. None will remain.
5. The waste products of nuclear fission
a. are harmless.
b. are safe after 20 years.
c. can be destroyed by burning them.
d. remain radioactive for thousands of years.
6. Which statement about nuclear fusion is NOT true?
a. Nuclear fusion occurs in the sun.
b. Nuclear fusion is the joining of the nuclei of atoms.
c. Nuclear fusion is currently used to generate electrical energy.
d. Nuclear fusion uses hydrogen as fuel.
7. An alpha particle is composed of two protons and
a. one neutron.
c. two electrons.
b. two neutrons.
d. one positron.
8. A beta particle has ____ than an alpha particle.
a. less energy
c. a greater positive charge
b. a larger mass
d. greater penetrating ability
9. After four half-lives have passed, ____ of the original sample remains.
a. one-sixteenth
c. one-eighth
b. one-fourth
d. none
10. Nuclear fusion
a. produces more radioactive waste than nuclear fission.
b. requires temperatures over 100,000,000ºC.
c. releases less energy per gram of fuel than nuclear fission.
d. is a more dangerous energy source than nuclear fission.
11. The generation of electrical energy by a nuclear power plant does NOT involve
a. using uranium-235 as fuel.
c. the production of carbon dioxide.
b. a controlled chain reaction.
d. the use of steam-driven turbines.
12. The energy emitted by the nuclei of some atoms in the form of high-energy particles and rays is called
a. nuclear radiation.
c. radioactive decay.
b. radioactivity.
d. activation energy.
13. The ability of some elements to give off nuclear radiation is referred to as
a. radioactive decay.
c. nuclear radiation.
b. radioactivity.
d. activation energy.
____ 14. The process in which the nucleus of a radioactive atom releases nuclear radiation is
a. nuclear decay.
c. radioactive decay.
b. activation energy.
d. radioactivity.
____ 15. Alpha decay occurs when ____ are released from a nucleus.
a. a proton and a neutron
c. positrons
b. two protons and two neutrons
d. electrons
____ 16. An alpha particle is the same thing as
a. an electron.
c. a helium atom.
b. a proton.
d. the nucleus of a helium atom.
____ 17. Which of the following give off alpha particles?
a. helium atoms
c. large radioactive nuclei
b. small radioactive nuclei
d. none of the above
____ 18. The sum of the protons and neutrons in an atom is the atom's
a. atomic number.
c. isotope number.
b. mass number.
d. ion number.
____ 19. During alpha decay,
a. the mass number is conserved.
c. an alpha particle is released.
b. charge is conserved.
d. All of the above
____ 20. Alpha and beta decay result in an element
a. increasing the mass number of its atoms.
b. undergoing the process of transmutation.
c. changing into another element.
d. Both (b) and (c)
____ 21. Beta decay occurs when ____ released from a nucleus.
a. a proton and a neutron are
c. gamma rays are
b. an electron or a positron is
d. a helium nucleus is
____ 22. The mass number of an alpha particle is
a. 0.
c. 2.
b. 1.
d. 4.
____ 23. The mass number of a beta particle is
a. 0.
c. 2.
b. 1.
d. 4.
____ 24. Gamma decay results in an element
a. remaining the same.
b. undergoing the process of transmutation.
c. changing into another element.
d. Both (b) and (c)
____ 25. Gamma decay occurs when ____ released from a nucleus.
a. a proton and a neutron are
c. light with very high energy is
b. an electron or a positron is
d. a helium nucleus is
____ 26. Which of the following has a charge of 1+ and almost no mass?
a. alpha particle
c. electron
b. positron
d. gamma ray
____ 27. Which of the following has a charge of 1– and almost no mass?
a. positron
c. electron
b. gamma ray
d. alpha particle
____ 28. ____ have neither charge nor mass.
a. Alpha particles
c. Electrons
b. Gamma rays
d. Positrons
____ 29. ____ are the most penetrating nuclear radiation.
a. Electrons
c. Alpha particles
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____ 44.
b. Gamma rays
d. Positrons
Which of the following travel about 1 m through air, but are stopped by 3 mm of aluminum?
a. alpha particles
c. gamma rays
b. beta particles
d. none of the above
Which of the following travel about 7 cm through air and are stopped by paper or clothing?
a. alpha particles
c. positrons
b. gamma rays
d. electrons
Nuclear radiation can cause damage to living matter because it can
a. knock electrons out of atoms.
c. damage the cells of an organism.
b. break chemical bonds between atoms.
d. All of the above
All nuclei composed of more than ____ protons are radioactive.
a. 75
c. 95
b. 83
d. 103
Which force prevents the protons in an atom's nucleus from flying apart?
a. strong force
c. electromagnetic force
b. weak force
d. gravitational force
Which of the following would most likely cause a nucleus with a mass number of 18 to be unstable?
a. The nucleus has 9 protons.
c. The nucleus has 9 neutrons.
b. The nucleus has 12 protons.
d. none of the above
How does a nucleus become stable?
a. It emits gamma rays.
c. It emits beta particles.
b. It emits alpha particles.
d. all of the above
Nuclei with more than 60 protons are stable when the ratio of neutrons to protons is about
a. 1 to 1.
c. 2 to 1.
b. 1 to 2.
d. 3 to 2.
Nuclei with less than 20 protons are stable when the ratio of neutrons to protons is about
a. 1 to 1.
c. 2 to 1.
b. 1 to 2.
d. 3 to 2.
Why does the percentage of carbon-14 in a living organism remain about the same?
a. Carbon-14 atoms cannot be replaced or destroyed.
b. Carbon-14 atoms that decay are replaced from the atmosphere or from food.
c. Carbon-14 cannot decay until an organism dies.
d. none of the above
When an organism dies, the carbon-14
a. is no longer replaced.
c. begins to decay.
b. is replaced at a much slower rate.
d. decays at a much faster rate.
The amount of time it takes for one-half of the nuclei of a radioactive isotope to decay is its
a. lifetime.
c. radioactive coefficient.
b. half-life.
d. radioactive constant.
The rate of decay of a radioactive sample
a. is affected by temperature.
c. is affected by surface area.
b. is affected by pressure.
d. is constant.
How many half-lives have passed if a sample contains one-sixteenth of its original amount of radioactive
material?
a. one
c. three
b. two
d. four
How many half-lives have passed if a sample contains one-fourth of its original amount of radioactive
material?
a. one
c. three
b. two
d. four
____ 45. One-fourth of an ivory carving's original carbon-14 remains unchanged. Carbon-14 has a half-life of 5,730
years. How old is the carving?
a. 1,432.5 years old
c. 5,730 years old
b. 4,297.5 years old
d. 11,460 years old
____ 46. A bowl carved out of bone is displayed in a museum. Half of its original carbon-14 has decayed. Carbon-14
has a half-life of 5,730 years. How old is the bowl?
a. 1,432.5 years old
c. 5,730 years old
b. 4,297.5 years old
d. 11,460 years old
____ 47. A human bone has been recently excavated from an archaeological dig. One-eighth of the bone's original
carbon-14 remains. Carbon-14 has a half-life of 5,730 years. How old is the bone?
a. 716 years old
c. 5,730 years old
b. 2,865 years old
d. 17,190 years old
____ 48. A mummy was recently discovered in a catacomb. Suppose half of the original carbon-14 atoms in the
mummy remain. Carbon-14 has a half-life of 5,730 years. How old is the mummy?
a. 5,730 years old
c. 1432.5 years old
b. 2,865 years old
d. 17,190 years old
____ 49. Potassium-40 has a half-life of 1.3 billion years. If the potassium-40 in a dinosaur bone was found to have
undergone one-tenth of a half-life, how old is the dinosaur bone?
a. 13 million years old
c. 1.3 billion years old
b. 130 million years old
d. 13 billion years old
____ 50. Which of the following uses radioactive isotopes?
a. smoke detectors
c. blenders
b. microwave ovens
d. radios
____ 51. Which of the following is NOT a use of radioactive isotopes?
a. killing cancer cells
b. powering a car
c. powering space probes
d. sterilizing food and health-care products
____ 52. Tracers are used to
a. determine how well plants respond to fertilizers.
b. diagnose medical problems.
c. find weak spots in materials.
d. All of the above
____ 53. The process in which a large nucleus splits into two smaller nuclei with the release of energy is
a. gamma decay.
c. nuclear fission.
b. alpha decay.
d. nuclear fusion.
____ 54. The nuclei of large atoms can be made to undergo nuclear fission by hitting them with
a. alpha particles.
c. gamma radiation.
b. beta particles.
d. neutrons.
____ 55. A nuclear chain reaction is a continuous series of
a. fusion reactions.
c. chemical reactions.
b. nuclear fission reactions.
d. Both (a) and (c)
____ 56. The energy of an atomic bomb is the result of a(n)
a. controlled chain reaction.
c. uncontrolled chain reaction.
b. controlled fusion reaction.
d. uncontrolled fusion reaction.
____ 57. Nuclear power plants use
a. uncontrolled fusion reactions.
c. controlled fusion reactions.
b. uncontrolled chain reactions.
d. controlled chain reactions.
____ 58. Which of the following is a benefit of using nuclear power?
a. Nuclear power plants are more expensive to build.
b. The supply of uranium is limited.
c. The use of nuclear power does not release harmful gases into the atmosphere.
____ 59.
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d. Nuclear waste can be stored anywhere.
The process in which two or more nuclei with small masses join together to form a larger, more massive
nucleus is called
a. alpha radiation.
c. nuclear fission.
b. gamma radiation.
d. nuclear fusion.
In order for fusion to occur, the repulsion between ____ must be overcome.
a. electrons
c. positively charged nuclei
b. neutrons
d. helium atoms
For fusion to occur, temperatures should be about the same temperature as
a. Earth's core.
c. the moon's core.
b. magma in Earth's mantle.
d. the sun's core.
What radioactive isotope is commonly used in nuclear power plants?
a. cobalt-60
c. uranium-235
b. hydrogen-3
d. polonium-210
Nuclear power plants have ____ and keep chain reactions at a safe level.
a. control rods to absorb protons
c. turbines to absorb protons
b. control rods to absorb neutrons
d. turbines to absorb neutrons
____ is often used to absorb energy from a chain reaction in a nuclear power plant.
a. Water
c. Carbon
b. Hydrogen peroxide
d. Uranium
When the coolant turns to steam in a nuclear power plant, the steam in turn
a. is piped to people's homes.
b. is sent to the city grid.
c. rises out of a tower into the atmosphere.
d. rotates a turbine.
____ converts the kinetic energy of a spinning turbine into electrical energy in a nuclear power plant.
a. A generator
c. A thermocouple
b. An insulator
d. A coolant
In the sun's core, hydrogen fuses to form
a. oxygen.
c. nitrogen.
b. carbon.
d. helium.
Energy for your home cannot yet be generated using nuclear fusion because
a. incredibly high temperatures are needed.
b. more energy is needed to create and contain the plasma than is produced by fusion.
c. it is very difficult to contain a plasma.
d. All of the above
What can contain a plasma?
a. a bottle made of radioactive material
c. a thick lead container
b. a strong magnetic field
d. a thick concrete container
The hydrogen-2 and hydrogen-3 isotopes to be used as fuel in nuclear fusion are commonly found
a. in magma.
c. in the atmosphere.
b. in the ocean.
d. in rock outcroppings.
If an explosion occurred, which of the following is a benefit of nuclear fusion reactors?
a. There would be very little release of radioactive materials.
b. There would be no release of radioactive materials.
c. Only sea water would be released.
d. all of the above
How does the amount of radioactive waste from using nuclear fusion as an energy source compare with the
amount from using nuclear fission as an energy source.
a. Nuclear fusion produces more waste than nuclear fission.
b. Nuclear fusion produces the same amount of waste as nuclear fission.
____ 73.
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____ 76.
____ 77.
____ 78.
c. Nuclear fusion produces less waste than nuclear fission.
d. Nuclear fusion produces no waste, and nuclear fission generates nuclear waste.
The energy that sustains most life on Earth is produced from
a. fission.
c. carbon-14 decay.
b. fusion.
d. tracers.
After 10 minutes, half of a sample of nitrogen-13 remains. What is the half-life of nitrogen-13?
a. 0.5 minutes
c. 5 minutes
b. 1 minutes
d. 10 minutes
Stars use hydrogen for fuel in a process called
a. radioactive decay.
c. fission.
b. nuclear decay.
d. fusion.
After 9.42 seconds, one-eighth of a sample of oxygen-21 remains unchanged. What is the half-life of oxygen21?
a. 1.57 seconds
c. 9.42 seconds
b. 3.14 seconds
d. 28.26 seconds
One-sixteenth of the original sample of hydrogen-3 remains. If the half-life of hydrogen-3 is 12.3 years, how
old is the sample?
a. 0.75 years
c. 49.2 years
b. 3 years
d. 196.8 years
How many half-lives have passed if a sample contains one sixty-fourth of its original amount of radioactive
material?
a. four
c. six
b. five
d. seven
____ 79. How many half-lives have passed if
of a sample's original amount of radioactive material remains
unchanged?
a. three
c. five
b. four
d. six
____ 80. Atomic nuclei emit radiation in order to
a. achieve atomic decay.
b. achieve a stable number of protons and neutrons.
c. go through one or more half-lives.
d. None of the above
____ 81. A nuclear chain reaction can be modeled by
a. a ball bouncing after it has been dropped.
b. table-tennis balls being shot out of a machine.
c. a rock rolling down a hill.
d. dominos knocking each other over.
Short Answer
82. Use the graph to answer the questions below:
a. What is the half-life of fermium-256? of fermium-251?
b. Which of these isotopes is more stable? Explain.
83. The image of a small purse, shown below, was made in a similar manner as Becquerel’s original experiment.
What conclusions can be drawn about the penetrating power of radiation from this image?
Examine the illustration below, and answer the questions that follow.
84. How many neutrons are in the nuclei of uranium-238 and thorium-234?
85. What type of radioactive decay is shown in the diagram? Explain your answer.