Question 1

How many alpha particles are emitted in the series of radioactive decay events from a U-238 nucleus to a Pb-206 nucleus?

Accepted Answer

A) 32 
B) 16 
C) 8 
D) 4 
A) 32 
B) 16 
C) 8 
D) 4

Question 2

Why does plutonium not occur in appreciable amounts in natural ore deposits?

Accepted Answer

A) Most naturally occurring plutonium deposits have already been depleted in the creation of nuclear weapons. 
B) Plutonium is strictly a human-made element. 
C) Any plutonium initially in the earth's crust has long since decayed. 
D) Plutonium loses electrons to form positively charged particles that have long since washed into the oceans. 
A) Most naturally occurring plutonium deposits have already been depleted in the creation of nuclear weapons. 
B) Plutonium is strictly a human-made element. 
C) Any plutonium initially in the earth's crust has long since decayed. 
D) Plutonium loses electrons to form positively charged particles that have long since washed into the oceans.

Question 3

Which process would release energy from gold, fission or fusion? From carbon?

Accepted Answer

A) gold: fission; carbon: fusion 
B) gold: fusion; carbon: fission 
C) gold: fission; carbon: fission 
D) gold: fusion; carbon: fusion 
A) gold: fission; carbon: fusion 
B) gold: fusion; carbon: fission 
C) gold: fission; carbon: fission 
D) gold: fusion; carbon: fusion

Question 4

Elements above uranium in the periodic table do not exist in any appreciable amounts in nature because they have short half-lives. Yet there are several elements below uranium in atomic number with equally short half-lives that do exist in appreciable amounts in nature. How can you account for this?

Accepted Answer

A) These are isotopes formed by living bodies. 
B) These isotopes were placed in nature by the testing of nuclear bombs. 
C) These isotopes were formed from the fusion of even smaller isotopes. 
D) These isotopes result from the radioactive decay of uranium. 
A) These are isotopes formed by living bodies. 
B) These isotopes were placed in nature by the testing of nuclear bombs. 
C) These isotopes were formed from the fusion of even smaller isotopes. 
D) These isotopes result from the radioactive decay of uranium.

Question 5

The element uranium (U, atomic no. = 92)often has 146 (or more)neutrons but it will still undergo radioactive decay. Which statement might best describe why?

Accepted Answer

A) The attractive force of the nucleons has a limited range. 
B) The isolated neutron is not stable and will undergo spontaneous transformation into a proton and an electron. 
C) The force is strong with U, but tainted with the dark side it is. 
D) both A and B 
E) none of the above 
A) The attractive force of the nucleons has a limited range. 
B) The isolated neutron is not stable and will undergo spontaneous transformation into a proton and an electron. 
C) The force is strong with U, but tainted with the dark side it is. 
D) both A and B 
E) none of the above

Question 6

Which of the beams is due to a high energy electron?

Accepted Answer

A) a 
B) b 
C) c 
D) all of the above 
E) none of the above 
A) a 
B) b 
C) c 
D) all of the above 
E) none of the above

Question 7

Which of the following statements about carbon-14 dating is true?

Accepted Answer

A) Carbon-14 dating is very accurate because the amount of carbon-14 in the atmosphere is constant. 
B) Carbon-14 can be used to date anything younger than 50,000 years. 
C) Carbon-14 dating can be used to date stone tools as well as bone. 
D) all of the above 
E) none of the above 
A) Carbon-14 dating is very accurate because the amount of carbon-14 in the atmosphere is constant. 
B) Carbon-14 can be used to date anything younger than 50,000 years. 
C) Carbon-14 dating can be used to date stone tools as well as bone. 
D) all of the above 
E) none of the above

Question 8

Just after an alpha particle leaves the nucleus, would you expect it to speed up? Why?

Accepted Answer

A) No. Once the alpha particle leaves the nucleus it is slowed by the repulsion of the next closest atom's nucleus. 
B) No. As the alpha particle leaves the nucleus it is slowed by the constant attraction of the electrons surrounding the nucleus. 
C) Yes. Once the alpha particle leaves the nucleus there are no more forces acting on it and it therefore accelerates. 
D) Yes. Once the alpha particle leaves the nucleus it accelerates because of mutual electric repulsion with the nucleus from which it escaped. 
A) No. Once the alpha particle leaves the nucleus it is slowed by the repulsion of the next closest atom's nucleus. 
B) No. As the alpha particle leaves the nucleus it is slowed by the constant attraction of the electrons surrounding the nucleus. 
C) Yes. Once the alpha particle leaves the nucleus there are no more forces acting on it and it therefore accelerates. 
D) Yes. Once the alpha particle leaves the nucleus it accelerates because of mutual electric repulsion with the nucleus from which it escaped.

Question 9

Which of the following statements about fusion is the most accurate?

Accepted Answer

A) The mass of the products is less than the mass of the reactants. 
B) The mass of the reactants is less than the mass of the products. 
C) A nuclear fusion will always release energy. 
D) Overcoming the strong nuclear force results in the release of a large amount of energy. 
E) Fission releases more energy than fusion. 
A) The mass of the products is less than the mass of the reactants. 
B) The mass of the reactants is less than the mass of the products. 
C) A nuclear fusion will always release energy. 
D) Overcoming the strong nuclear force results in the release of a large amount of energy. 
E) Fission releases more energy than fusion.

Question 10

Where does the earth receive most of its energy?

Accepted Answer

A) external fusion 
B) internal fusion 
C) internal fission 
D) external fission 
E) internal combustion 
A) external fusion 
B) internal fusion 
C) internal fission 
D) external fission 
E) internal combustion

Question 11

In the 19th century the famous physicist Lord Kelvin estimated the age of Earth to be much much less than its present estimate. What information did Kelvin not have to account for his error?

Accepted Answer

A) Lord Kelvin knew only classical physics and had no knowledge of anthropological dating. 
B) Lord Kelvin had no knowledge of radio waves for measuring distance and age of planets since they have not yet been introduced into science. 
C) Lord Kelvin was not aware of radioactive decay, a source of energy to keep Earth warm for billions of years. 
D) Lord Kelvin never gave any estimate of the age of Earth. 
A) Lord Kelvin knew only classical physics and had no knowledge of anthropological dating. 
B) Lord Kelvin had no knowledge of radio waves for measuring distance and age of planets since they have not yet been introduced into science. 
C) Lord Kelvin was not aware of radioactive decay, a source of energy to keep Earth warm for billions of years. 
D) Lord Kelvin never gave any estimate of the age of Earth.

Question 12

Light nuclei can be split. For example, a deuteron, which is a proton-neutron combination, can split into a separate proton and separate neutron. Does such a process yield energy or cost energy? Why?

Accepted Answer

A) Yields energy. Splitting nuclei of any sort is a basic example of a nuclear reaction releasing massive amounts of energy. 
B) Neither. The amount of energy required to split the light nuclei is exactly the same as that released. This is the basis of the Law of Conservation of Energy. 
C) Costs energy. This fact is consistent with the sum of the masses of the separated proton and neutron being greater than the mass of the original deuteron. 
D) Yields energy. This fact is consistent with the sum of the masses of the separated proton and neutron being less than the mass of the original deuteron. 
A) Yields energy. Splitting nuclei of any sort is a basic example of a nuclear reaction releasing massive amounts of energy. 
B) Neither. The amount of energy required to split the light nuclei is exactly the same as that released. This is the basis of the Law of Conservation of Energy. 
C) Costs energy. This fact is consistent with the sum of the masses of the separated proton and neutron being greater than the mass of the original deuteron. 
D) Yields energy. This fact is consistent with the sum of the masses of the separated proton and neutron being less than the mass of the original deuteron.

Question 13

If uranium were to split into three segments of equal size instead of two, would more energy or less energy be released?

Accepted Answer

A) Less energy would be released because of less mass per nucleon. 
B) Less energy would be released because of more mass per nucleon. 
C) More energy would be released because of less mass per nucleon 
D) More energy would be released because of more mass per nucleon. 
A) Less energy would be released because of less mass per nucleon. 
B) Less energy would be released because of more mass per nucleon. 
C) More energy would be released because of less mass per nucleon 
D) More energy would be released because of more mass per nucleon.

Question 14

Which of the following nuclear equations correctly describes beta emission?

Accepted Answer

A)    U →   Th +   He 
B)    U →   U +   He 
C)    U →   Pu +   He 
D)    U →   He 
E) none of the above 
A)    U →   Th +   He 
B)    U →   U +   He 
C)    U →   Pu +   He 
D)    U →   He 
E) none of the above

Question 15

Why would you expect alpha particles to be less able to penetrate materials than beta particles of the same kinetic energy?

Accepted Answer

A) Alpha particles pick up electrons to become harmless helium atoms. 
B) Alpha particles carry twice the electric charge. 
C) Alpha particles move much slower for a given kinetic energy. 
D) Two of the above answers are reasonable. 
A) Alpha particles pick up electrons to become harmless helium atoms. 
B) Alpha particles carry twice the electric charge. 
C) Alpha particles move much slower for a given kinetic energy. 
D) Two of the above answers are reasonable.

Question 16

Which of the following nuclear equations correctly describes alpha emission?

Accepted Answer

A)    U →   Th +   He 
B)    U →   U +   He 
C)    U →   Pu +   He 
D)    U →   He 
E) none of the above 
A)    U →   Th +   He 
B)    U →   U +   He 
C)    U →   Pu +   He 
D)    U →   He 
E) none of the above

Question 17

Explain how radioactive decay has always warmed the earth from the inside, and nuclear fusion has always warmed the earth from the outside.

Accepted Answer

A) Much heat was released as matter coalesced to form the earth. This heat resulted in the production of radioactive isotopes, which still reside within the earth today and are a source of internal heat. Our primary external source of heat is from the fusion of hydrogen within the sun. 
B) The inner Earth is made of fissioning heavy elements while the sun is made of lighter fusing elements. 
C) Radioactive elements have been within Earth since it was created while the sun is made of fusing hydrogen atoms. 
D) All of the above are reasonable answers. 
A) Much heat was released as matter coalesced to form the earth. This heat resulted in the production of radioactive isotopes, which still reside within the earth today and are a source of internal heat. Our primary external source of heat is from the fusion of hydrogen within the sun. 
B) The inner Earth is made of fissioning heavy elements while the sun is made of lighter fusing elements. 
C) Radioactive elements have been within Earth since it was created while the sun is made of fusing hydrogen atoms. 
D) All of the above are reasonable answers.

Question 18

If a nucleus of   Th absorbs a neutron and the resulting nucleus undergoes two successive beta decays (emitting electrons), what nucleus results?

Accepted Answer

A) americium-232 
B) plutonium-232 
C) thorium-233 
D) uranium-233 
A) americium-232 
B) plutonium-232 
C) thorium-233 
D) uranium-233

Question 19

Alpha and beta rays are deflected in opposite directions in a magnetic field because

Accepted Answer

A) they have opposite charges. 
B) they spin in opposite directions. 
C) alpha particles contain nucleons and beta particles do not. 
D) all of the above 
A) they have opposite charges. 
B) they spin in opposite directions. 
C) alpha particles contain nucleons and beta particles do not. 
D) all of the above

Question 20

Which type of radiation-alpha, beta, or gamma-results in the least change in atomic number?

Accepted Answer

A) alpha radiation 
B) beta radiation 
C) gamma radiation 
D) They all result in the same change in atomic mass number. 
A) alpha radiation 
B) beta radiation 
C) gamma radiation 
D) They all result in the same change in atomic mass number.

Exam 13: The Atomic Nucleus and Radioactivity

How many alpha particles are emitted in the series of radioactive decay events from a U-238 nucleus to a Pb-206 nucleus?

Why does plutonium not occur in appreciable amounts in natural ore deposits?

Which process would release energy from gold, fission or fusion? From carbon?

The element uranium (U, atomic no. = 92)often has 146 (or more)neutrons but it will still undergo radioactive decay. Which statement might best describe why?

Which of the beams is due to a high energy electron?

Which of the following statements about carbon-14 dating is true?

Just after an alpha particle leaves the nucleus, would you expect it to speed up? Why?

Which of the following statements about fusion is the most accurate?

Where does the earth receive most of its energy?

In the 19th century the famous physicist Lord Kelvin estimated the age of Earth to be much much less than its present estimate. What information did Kelvin not have to account for his error?

Light nuclei can be split. For example, a deuteron, which is a proton-neutron combination, can split into a separate proton and separate neutron. Does such a process yield energy or cost energy? Why?

If uranium were to split into three segments of equal size instead of two, would more energy or less energy be released?

Which of the following nuclear equations correctly describes beta emission?

Why would you expect alpha particles to be less able to penetrate materials than beta particles of the same kinetic energy?

Which of the following nuclear equations correctly describes alpha emission?

Explain how radioactive decay has always warmed the earth from the inside, and nuclear fusion has always warmed the earth from the outside.

If a nucleus of Th absorbs a neutron and the resulting nucleus undergoes two successive beta decays (emitting electrons), what nucleus results?

Alpha and beta rays are deflected in opposite directions in a magnetic field because

Which type of radiation-alpha, beta, or gamma-results in the least change in atomic number?

Patterns of Motion and Equilibrium

Newtons Laws of Motion

Momentum and Energy

Gravity, Projectiles, and Satellites

Fluid Mechanics

Thermal Energy and Thermodynamics

Heat Transfer and Change of Phase

Static and Current Electricity

Magnetism and Electromagnetic Induction

Waves and Sound

Light

Atoms and the Periodic Table

Elements of Chemistry

How Atoms Bond and Molecules Attract

Mixtures

How Chemicals React

Two Classes of Chemical Reactions

Organic Compounds

Rocks and Minerals

Plate Tectonics and Earths Interior

Shaping Earths Surface

Geologic Timereading the Rock Record

The Oceans, Atmosphere, and Climatic Effects

Driving Forces of Weather

The Solar System

Stars and Galaxies

The Structure of Space and Time

Prologue: the Nature of Science

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