Question 1

A pair of protons in an atomic nucleus repel each other,but they are also attracted to each other.Why?

Accepted Answer

A) The pair repel each other by nuclear force but attract one another by an electrical force. 
B) The pair repel each other since they are both positively charges but they are held together by much stronger forces known as quarks. 
C) The pair attract each other by nuclear force but also repel one another by a weaker electrical force. 
D) Although it is known that protons repel each other at short distances because of like charge,it is not known what actually holds protons together in the nucleus because we have never seen the nucleus of an atom. 
A) The pair repel each other by nuclear force but attract one another by an electrical force. 
B) The pair repel each other since they are both positively charges but they are held together by much stronger forces known as quarks. 
C) The pair attract each other by nuclear force but also repel one another by a weaker electrical force. 
D) Although it is known that protons repel each other at short distances because of like charge,it is not known what actually holds protons together in the nucleus because we have never seen the nucleus of an atom. C

Question 2

Complete the following nuclear equation: ?? ? $\begin{array} { c } 
222\
86
\end{array}$ Rn + $\begin{array} { c } 
4\
2
\end{array}$ He

Accepted Answer

A)  $\begin{array} { c } 
226 \
88
\end{array}$ Ra 
B)  $\begin{array} { l } 
222 \
85
\end{array}$ At 
C)  $\begin{array} { c } 
218\
84
\end{array}$ Po 
D)  $\begin{array} { c } 
222\
86
\end{array}$ Rn 
E) none of the above 
A)  $\begin{array} { c } 
226 \
88
\end{array}$ Ra 
B)  $\begin{array} { l } 
222 \
85
\end{array}$ At 
C)  $\begin{array} { c } 
218\
84
\end{array}$ Po 
D)  $\begin{array} { c } 
222\
86
\end{array}$ Rn 
E) none of the above A

Question 3

Which of the following is a major disadvantage of nuclear-fission-based power plants?

Accepted Answer

A) The reactors can be used to produce their own fuel. 
B) The byproducts of the fission process are radioactive and have very long half-lives. 
C) The amount of energy per kilogram of fuel is greater than any other fuel source. 
D) The power plants are complex and there are many safety requirements to prevent contamination of the environment. 
E) B and D 
A) The reactors can be used to produce their own fuel. 
B) The byproducts of the fission process are radioactive and have very long half-lives. 
C) The amount of energy per kilogram of fuel is greater than any other fuel source. 
D) The power plants are complex and there are many safety requirements to prevent contamination of the environment. 
E) B and D E

Question 4

A friend produces a Geiger counter to check the local background radiation.It ticks.Another friend,who normally fears most that which is understood least,makes an effort to keep away from the region of the Geiger counter and looks to you for advice.What do you say?

Accepted Answer

A) Run away as fast as you can! 
B) The Geiger counter is emitting radiation. 
C) The Geiger counter is detecting naturally occurring radiation from your body. 
D) Wear heavy clothes. 
A) Run away as fast as you can! 
B) The Geiger counter is emitting radiation. 
C) The Geiger counter is detecting naturally occurring radiation from your body. 
D) Wear heavy clothes.

Question 5

Which of the following statements about fission is true?

Accepted Answer

A) The amount of energy released in the fission of large nuclei is very large. 
B) The amount of energy released in the fusion of small nuclei is very large. 
C) Bombarding a nucleus with neutrons always leads to fission. 
D) The fragments of a fusion reaction are always the same size. 
E) none of the above 
A) The amount of energy released in the fission of large nuclei is very large. 
B) The amount of energy released in the fusion of small nuclei is very large. 
C) Bombarding a nucleus with neutrons always leads to fission. 
D) The fragments of a fusion reaction are always the same size. 
E) none of the above

Question 6

You and your friend journey to the mountain foothills to get closer to nature and escape such things as radioactivity.While bathing in the warmth of a natural hot spring she wonders aloud how the spring gets its heat.What do you tell her? You tell her that the hot water is the result of

Accepted Answer

A) industrial thermal pollution. 
B) radioactivity. 
C) chemical reactions involving the atomic nucleus. 
D) nuclear fission. 
A) industrial thermal pollution. 
B) radioactivity. 
C) chemical reactions involving the atomic nucleus. 
D) nuclear fission.

Question 7

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 8

Does a radioactive isotope ever lose its radioactivity?

Accepted Answer

A) yes 
B) no 
C) sometimes 
D) usually 
A) yes 
B) no 
C) sometimes 
D) usually

Question 9

Why doesn't uranium ore spontaneously undergo a chain reaction?

Accepted Answer

A) Uranium ore must be "weapons' grade" in order for it to undergo chain reaction. 
B) Uranium ore is mostly non-fissionable isotope U-238 and undergoes a chain reaction only if mixed with a moderator to slow down the neutrons. 
C) Uranium ore does spontaneously undergo slow chain reaction over time finally resulting in it becoming lead. 
D) Uranium ore,mostly U-235,must be enriched with U-238 in order for it to undergo a chain reaction. 
A) Uranium ore must be "weapons' grade" in order for it to undergo chain reaction. 
B) Uranium ore is mostly non-fissionable isotope U-238 and undergoes a chain reaction only if mixed with a moderator to slow down the neutrons. 
C) Uranium ore does spontaneously undergo slow chain reaction over time finally resulting in it becoming lead. 
D) Uranium ore,mostly U-235,must be enriched with U-238 in order for it to undergo a chain reaction.

Question 10

How come an animal's carbon-14 levels do not start to decrease until it dies?

Accepted Answer

A) because it constantly replenishes its carbon-14 supply by eating plants with carbon-14 in them 
B) because it constantly replenishes its carbon-14 supply by breathing air with carbon-14 in it 
C) because it is constantly being bombarded with cosmic rays 
D) carbon-14 only starts to decay after the animal dies 
E) the carbon-14 levels do not decrease because the carbon-13 in its skin protects it from cosmic rays 
A) because it constantly replenishes its carbon-14 supply by eating plants with carbon-14 in them 
B) because it constantly replenishes its carbon-14 supply by breathing air with carbon-14 in it 
C) because it is constantly being bombarded with cosmic rays 
D) carbon-14 only starts to decay after the animal dies 
E) the carbon-14 levels do not decrease because the carbon-13 in its skin protects it from cosmic rays

Question 11

Does the average distance that a neutron travels through fissionable material before escaping increase or decrease when two pieces of fissionable material are assembled into one piece? Does this assembly increase or decrease the probability of an explosion?

Accepted Answer

A) The average distance increases while the probability of an explosion also increases. 
B) The average distance decreases while the probability of an explosion decreases. 
C) The average distance increases while the probability of an explosion decreases. 
D) The average distance decreases while the probability of an explosion increases. 
A) The average distance increases while the probability of an explosion also increases. 
B) The average distance decreases while the probability of an explosion decreases. 
C) The average distance increases while the probability of an explosion decreases. 
D) The average distance decreases while the probability of an explosion increases.

Question 12

Which of the following statements about chain reactions is true?

Accepted Answer

A) The key requirement for a chain reaction is that more neutrons are produced than are absorbed. 
B) Three or more neutrons must be released to sustain a chain reaction. 
C) Only uranium isotopes are capable of supporting a chain reaction. 
D) It is not possible to stop or control a chain reaction once it has been started. 
E) A chain reaction will only take place when a critical mass of material has been assembled. 
A) The key requirement for a chain reaction is that more neutrons are produced than are absorbed. 
B) Three or more neutrons must be released to sustain a chain reaction. 
C) Only uranium isotopes are capable of supporting a chain reaction. 
D) It is not possible to stop or control a chain reaction once it has been started. 
E) A chain reaction will only take place when a critical mass of material has been assembled.

Question 13

Which of the following statements regarding a nucleon is true?

Accepted Answer

A) Attraction between nucleons changes their mass. 
B) The mass of a nucleon depends on which nucleus it is in. 
C) Some of the mass of a nucleon can be converted into energy by breaking certain nuclei. 
D) both A and C 
E) all of the above 
A) Attraction between nucleons changes their mass. 
B) The mass of a nucleon depends on which nucleus it is in. 
C) Some of the mass of a nucleon can be converted into energy by breaking certain nuclei. 
D) both A and C 
E) all of the above

Question 14

What does Einstein's energy equation (E = mc2)say about the energy that is derived from nuclear fission reactions?

Accepted Answer

A) The energy released is due to the missing mass of the products compared to the mass of the starting materials. 
B) The energy is proportional to the mass of the atom undergoing fission. 
C) The energy is derived from the light that is emitted when the atom splits. 
D) The energy equation does not apply towards fission,only fusion. 
E) none of the above 
A) The energy released is due to the missing mass of the products compared to the mass of the starting materials. 
B) The energy is proportional to the mass of the atom undergoing fission. 
C) The energy is derived from the light that is emitted when the atom splits. 
D) The energy equation does not apply towards fission,only fusion. 
E) none of the above

Question 15

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 16

Complete the following nuclear equation: ?? ? $\begin{array} { c } 
218\
85
\end{array}$ At + $\begin{array} { c } 
0 \
- 1
\end{array}$ e

Accepted Answer

A)  $\begin{array} { c } 
226 \
88
\end{array}$ Ra 
B)  $\begin{array} { l } 
222 \
85
\end{array}$ At 
C)  $\begin{array} { c } 
218\
84
\end{array}$ Po 
D)  $\begin{array} { c } 
222\
86
\end{array}$ Rn 
E) none of the above 
A)  $\begin{array} { c } 
226 \
88
\end{array}$ Ra 
B)  $\begin{array} { l } 
222 \
85
\end{array}$ At 
C)  $\begin{array} { c } 
218\
84
\end{array}$ Po 
D)  $\begin{array} { c } 
222\
86
\end{array}$ Rn 
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

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.

Question 19

After a uranium fuel rod reaches the end of its fuel cycle (typically 3 years)most of its energy comes from the fissioning of plutonium because

Accepted Answer

A) fissionable Pu-239 is formed as the U-238 absorbs neutrons from the fissioning U-235. 
B) fissionable Pu-239 is formed as the U-235 absorbs neutrons from the fissioning U-238. 
C) fissionable Pu-239 is formed as the U-238 absorbs alpha particles from the fissioning U-235. 
D) fissionable Pu-239 is formed as the U-235 absorbs alpha particles from the fissioning U-238. 
A) fissionable Pu-239 is formed as the U-238 absorbs neutrons from the fissioning U-235. 
B) fissionable Pu-239 is formed as the U-235 absorbs neutrons from the fissioning U-238. 
C) fissionable Pu-239 is formed as the U-238 absorbs alpha particles from the fissioning U-235. 
D) fissionable Pu-239 is formed as the U-235 absorbs alpha particles from the fissioning U-238.

Question 20

The image below shows a beam of radiation passing between two electrically charged plates.  
-Which of the beams is due to alpha particles?

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

Exam 13: The Atomic Nucleus and Radioactivity

A pair of protons in an atomic nucleus repel each other,but they are also attracted to each other.Why?

Complete the following nuclear equation: ?? ? 222 86 Rn + 4 2 He

Which of the following is a major disadvantage of nuclear-fission-based power plants?

A friend produces a Geiger counter to check the local background radiation.It ticks.Another friend,who normally fears most that which is understood least,makes an effort to keep away from the region of the Geiger counter and looks to you for advice.What do you say?

Which of the following statements about fission is true?

You and your friend journey to the mountain foothills to get closer to nature and escape such things as radioactivity.While bathing in the warmth of a natural hot spring she wonders aloud how the spring gets its heat.What do you tell her? You tell her that the hot water is the result of

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

Does a radioactive isotope ever lose its radioactivity?

Why doesn't uranium ore spontaneously undergo a chain reaction?

How come an animal's carbon-14 levels do not start to decrease until it dies?

Does the average distance that a neutron travels through fissionable material before escaping increase or decrease when two pieces of fissionable material are assembled into one piece? Does this assembly increase or decrease the probability of an explosion?

Which of the following statements about chain reactions is true?

Which of the following statements regarding a nucleon is true?

What does Einstein's energy equation (E = mc2)say about the energy that is derived from nuclear fission reactions?

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

Complete the following nuclear equation: ?? ? 218 85 At + 0 -1 e

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

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

After a uranium fuel rod reaches the end of its fuel cycle (typically 3 years)most of its energy comes from the fissioning of plutonium because

The image below shows a beam of radiation passing between two electrically charged plates. -Which of the beams is due to alpha particles?

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 Time - Reading 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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What does Einstein's energy equation (E = mc²)say about the energy that is derived from nuclear fission reactions?