Deck 29: Nuclear Physics

Question 1

¹⁶O, ¹⁷O, and ¹⁸O are ________ of oxygen.

A) isotones
B) isotopes
C) isobars
D) isomers
E) isotherms

Answer 1

isotopes

Question 2

What is the radius of a nuclide with mass number 190?

A) 190 fm
B) 5.7 fm
C) 6.9 fm
D) 4.8 fm
E) 0.19 fm

Answer 2

6.9 fm

Question 3

One mole of has a mass of approximately

A) 13 g
B) 27 g
C) 14 g
D) 20 g
E) 40 g

Answer 3

27 g

Question 4

One mole of ⁴⁰Ar (Z = 18) has about what mass?

A) 18 g
B) 22 g
C) 40 kg
D) 40 g
E) 22 kg

Question 5

Isotopes of an element have the same number of ________ but different numbers of _______.

A) neutrons, protons
B) electrons, protons
C) protons, neutrons
D) neutrons, electrons
E) protons, electrons

Question 6

What is the symbol for the nuclide with 38 protons and 50 neutrons?

A)
B)
C)
D)

Question 7

How many neutrons are in a ³⁵Cl nucleus?

A) 17
B) 18
C) 16
D) 19

Question 8

In the reaction n + ¹²C → α + ?, what is the unknown product nucleus?

A) (¹³C)
B) (⁹C)
C) (¹⁰B)
D) (⁹B)
E) (⁹Be)

Question 9

How many neutrons are in a ¹⁵C nucleus?

A) 7
B) 8
C) 6
D) 9

Question 10

What nuclide has 14 protons and 16 neutrons?

A) (¹⁶S)
B) (¹⁴O)
C) (³⁰Si)
D) (³⁰S)

Question 11

In the reaction ⁴He + ⁹Be → n + ¹²C, how much energy is released or absorbed? The masses of the neutral atoms are as follows: the mas of ⁴He is 4.0026033 u, the mass of ⁹Be is 9.0121831 u, the mass of n is 1.0086649 u, and the mass of ¹²C is 12.0000000 u.

A) 4.21 MeV absorbed
B) 4.21 MeV released
C) 5.70 MeV absorbed
D) 5.70 MeV released
E) 6.34 MeV released

Question 12

What is the density of the ²³⁸U nucleus?

A) 2.3 × 10¹⁷ kg/m³
B) 9.6 × 10¹⁴ kg/m³
C) 3.2 × 10¹⁴ kg/m³
D) 2.38 × 10⁵ kg/m³
E) 1.0 × 10³ kg/m³

Question 13

What is the volume of the nucleus?

A) 6.7 × 10^-43 m³
B) 5.2 × 10^-42 m³
C) 1.7 × 10^-42 m³
D) 1.6 × 10^-42 m³
E) 1.2 × 10^-12 m³

Question 14

What is the symbol for the nuclide with 46 protons and 92 neutrons?

A)
B)
C)
D)

Question 15

How many atoms are in one gram of ?

A) 1.63 × 10²⁵
B) 6.02 × 10²²
C) 1.51 × 10²³
D) 2.23 × 10²⁵
E) 2.23 × 10²²

Question 16

One pg (picogram) of ⁴⁰K has how many nuclei?

A) 6.0 × 10¹⁷
B) 6.0 × 10¹¹
C) 1.5 × 10²²
D) 3.0 × 10¹¹
E) 1.5 × 10¹⁰

Question 17

The particles in the nucleus referred to as nucleons are

A) electrons and protons.
B) protons and neutrons.
C) neutrons and electrons.
D) electrons and photons.

Question 18

If a nucleus has a volume of 1.0 × 10^-42 m³, what is its mass number?

A) 1
B) 25
C) 100
D) 138
E) 174

Question 19

What is the element X for the nuclide ?

A) Zn
B) Se
C) Gd
D) Ge

Question 20

A nuclide whose "generic" symbol is would have how many protons and neutrons, respectively?

A) 64, 30
B) 30, 64
C) 30, 34
D) 34, 30

Question 21

Of the following quantities, which (if any) is not conserved in radioactive decay?

A) energy
B) momentum
C) charge
D) angular momentum
E) All these quantities are conserved.

Question 22

What is the binding energy of an alpha particle?

A) 2.20 MeV
B) 50.0 MeV
C) 28.3 MeV
D) 21.2 MeV

Question 23

In the nucleus, what are the maximum number of neutrons in a neutron energy level, and the maximum number of protons in a proton energy level, respectively?

A) 1, 1
B) 1, 2
C) 2, 1
D) 2, 2
E) 2, 8

Question 24

The isotope A₂₈1 decays by beta-minus decay. What is the daughter nucleus?

A) Mg₂₈
B) A₂₇1
C) Na₂₄
D) Si₂₈
E) Si₂₇

Question 25

Of those elements listed below, the binding energy per nucleon reaches a maximum closest to

A) oxygen.
B) iron.
C) gold.
D) tungsten.
E) uranium.

Question 26

Who discovered radioactivity?

A) Niels Bohr
B) Marie Curie
C) Albert Einstein
D) Henri Becquerel
E) Richard Feynman

Question 27

The isotope A₂₆1 decays by beta-plus decay. What is the daughter nucleus?

A) (²⁷Al)
B) (²⁵Al)
C) (²⁶Mg)
D) (²⁶Si)
E) (²⁶Al)

Question 28

The majority of the average yearly radiation exposure from nonmedical sources, for people living in the United States, comes from

A) eating bananas.
B) cosmic rays.
C) naturally occurring uranium.
D) radon gas.
E) smoke detectors.

Question 29

In beta-minus decay, which neutrino is emitted?

A) the electron neutrino
B) the electron antineutrino
C) the muon neutrino
D) the muon antineutrino
E) the tau neutrino

Question 30

What is the binding energy per nucleon for ¹²C?

A) 137 MeV
B) 104 MeV
C) 92.2 MeV
D) 46.1 MeV
E) 7.68 MeV

Question 31

When ²⁴¹ Am decays by emitting an alpha particle of kinetic energy 5.5 MeV, what is the recoil energy of the daughter nucleus?

A) 5.5 MeV
B) 1.3 MeV
C) 0.88 MeV
D) 0.093 MeV
E) 0.091 MeV

Question 32

The symbol is used to represent the

A) proton
B) positron
C) antiproton
D) neutrino
E) electron

Question 33

Manganese-67 is an unstable nuclide. Which type of radioactive decay is it most likely to undergo?

A) gamma decay
B) β⁺decay
C) β⁻ decay
D) α decay
E) spontaneous fission

Question 34

Radium-226 decays by alpha decay. What are A and Z for the daughter nuclide?

A) 226, 92
B) 222, 92
C) 226, 88
D) 222, 88
E) 222, 86

Question 35

The neutrino was proposed by Wolfgang Pauli to overcome the apparent violation of which of the following conservation laws in beta decay?

A) energy
B) momentum
C) energy and momentum
D) charge
E) energy, momentum, and charge

Question 36

What are the approximate binding energies per nucleon (in MeV) around A = 60 and A = 240, respectively?

A) 9.4, 7.0
B) 7.6, 8.7
C) 7.0, 9.4
D) 7.0, 8.0
E) 8.7, 7.6

Question 37

What is the binding energy of ¹²C? The mass of an atom of ¹²C is 12 u (exactly), the mass of an atom of ¹H is 1.007825 u, and the mass of a neutron is 1.0086649 u.

A) 137 MeV
B) 104 MeV
C) 92.2 MeV
D) 46.1 MeV
E) 7.68 MeV

Question 38

What is the mass defect of an alpha particle?

A) 0.03038 u
B) 0.30377 u
C) 0.03147 u
D) 0.02928 u

Question 39

The three most common types of radiation emitted by radioactive nuclei were originally named alpha, beta, and gamma rays, after the first letters of the Greek alphabet. In order of increasing ability to penetrate matter, these are

A) alpha, beta, gamma.
B) beta, gamma, alpha.
C) gamma, alpha, beta.
D) alpha, gamma, beta.
E) gamma, beta, alpha.

Question 40

A unstable medium-sized nucleus with an equal number of protons and neutrons (Z = N) is most likely to decay via

A) gamma decay
B) β⁺ decay
C) β⁻ decay
D) α decay
E) spontaneous fission

Question 41

A sample contains 1.000 × 10⁻³ g of ⁴⁰K. The half-life of ⁴⁰K is 1.250 × 10⁹ years. What is the activity of the sample?

A) 3300 Bq
B) 1250 Bq
C) 382.0 Bq
D) 265.0 Bq
E) 3.000 Bq

Question 42

The quantum-mechanical process by which an alpha particle makes it through the potential barrier holding it in the nucleus is called

A) leaping.
B) tunneling.
C) transmission.
D) fission.
E) transportation.

Question 43

If a 70 kg person received a dose of 3.2 mGy of gamma rays of RBE = 0.80, what is the biologically equivalent dose in rem?

A) 0.012
B) 0.18
C) 0.0026
D) 0.26
E) 18

Question 44

Carbon-14 has an activity of 0.25 Bq per gram of carbon for living organisms. The half-life of ¹⁴C is 5730 years. If a sample of charcoal from an archeological dig yields a ¹⁴C activity of 0.15 Bq per gram of carbon, how old is the material?

A) 6.6 × 10³ y
B) 5.1 × 10³ y
C) 4.2 × 10³ y
D) 1.7 × 10³ y
E) 1.4 × 10³ y

Question 45

In radiation dosage, the factor that accounts for the impact of the type of radiation on the biological damage caused is the

A) absorbed dose.
B) biologically equivalent dose.
C) disintegration energy.
D) relative biological effectiveness.
E) mass defect.

Question 46

The half-life of ³⁰P is 2.50 minutes. If a sample of ³⁰P has 1.60 × 10¹⁰ nuclei present, what is its activity?

A) 4.6 × 10⁷ Bq
B) 7.4 × 10⁷ Bq
C) 6.4 × 10⁹ Bq
D) 1.6 × 10¹⁰ Bq
E) 1.6 × 10⁹ Bq

Question 47

A neutron star has approximately the same density as nuclear material. A typical neutron star has a radius of 8.0 km. Using the relationship r = (1.2 fm) A^1/3 together with the mass of a neutron, 1.67 × 10⁻²⁷kg, estimate the mass of a neutron star.

A) 0.65 × 10³⁰ kg
B) 1.5 × 10³⁰ kg
C) 0.16 × 10³⁰ kg
D) 0.49 × 10³⁰ kg

Question 48

If a nucleus has excited states above the ground state at energies 300 keV, 200 keV, and 80 keV, what gamma rays (in keV) may be expected from a collection of these excited nuclei? The ground-state energy is at 0. Choose the most complete set.

A) 300, 200, 80
B) 300, 200, 120, 80
C) 100, 120, 80
D) 300, 120, 200, 80, 180
E) 300, 220, 200, 120, 100, 80

Question 49

It is common to illustrate the density of nuclear matter by discussing the mass of a teaspoon of nuclear material. The volume of a teaspoon is about 5 cm³. Using the relationship r = (1.2 fm) A^1/3 together with the mass of a proton, 1.67 × 10⁻²⁷ kg, estimate the mass of a teaspoon of nuclear material.

A) 3.8 × 10¹¹ kg
B) 9.6 × 10¹¹kg
C) 1.53 × 10¹² kg
D) 1.15 × 10¹² kg

Question 50

The fusion reaction ²H + ³H → ⁴He + n releases 17.6 MeV of energy. The mass of ²H is 2.01410 u, the mass of ⁴He is 4.00260 u, and the mass of the neutron is 1.00866 u. What is the mass of ³H?

A) 2.9972 u
B) 3.0161 u
C) 3.0349 u
D) 3.0422 u
E) 2.9998 u

Question 51

If a nuclide has a half-life of 100 s, what is the corresponding mean lifetime?

A) 100 s
B) 144 s
C) 69 s
D) 50 s
E) 75 s

Question 52

The tokamak is a device designed to produce

A) tritium.
B) lithium hydride pellets.
C) carbon cycles.
D) controlled fission.
E) controlled fusion.

Question 53

A nuclear reactor periodically emits radioactive isotopes that travel outward at a speed of 1.0 km/s. If these isotopes have a half-life of 12 ms, what is the average distance they travel before decaying?

A) 12 μm
B) 12 m
C) 17 m
D) 1.0 km
E) 83 km

Question 54

What is the ratio of radii of the nuclides and ?

A) 1.66
B) 2.44
C) 5.95
D) 1.81

Question 55

What is the mass of 25.0 mCi of technetium-99m (Tc_99m), which has a half-life of 6.00 h?

A) 4.74 ng
B) 50.7 pg
C) 1.05 ng
D) 3.29 ng
E) 25.0 mg

Question 56

If a 60 kg person received a biologically equivalent dose of 1.7 rem of radiation with an RBE of 1.1, what was the total energy absorbed by the person?

A) 1.7 J
B) 1.5 J
C) 0.93 J
D) 0.015 J
E) 0.26 J

Question 57

A beam of gamma rays strikes a lead target with a half-value layer of 0.40 cm. What fraction of the photons in the beam will penetrate to a depth of 1.20 cm or more?

A) 0.500
B) 0.400
C) 0.333
D) 0.250
E) 0.125

Question 58

In the fission reaction n + → + ? + 4n, what are the Z and A for the unknown fission product?

A) 37, 90
B) 35, 94
C) 36, 90
D) 37, 91
E) 36, 91

Question 59

The half-life of ³⁰P is 2.50 minutes. If a sample of ³⁰P has 1.60 × 10¹⁰ nuclei present initially, how many remain after 10.0 minutes?

A) 0.800 × 10¹⁰
B) 0.400 × 10¹⁰
C) 0.200 × 10¹⁰
D) 0.100 × 10¹⁰
E) 0.050 × 10¹⁰

Question 60

Barium-137 emits a gamma ray in the decay from an excited state (¹³⁷Ba^*). What is the resulting daughter nuclide?

A) (¹³⁷Cs)
B)( ¹³⁷Ba)
C)( ¹³⁷La)
D)( ¹³⁶Ba)
E) (¹³⁶Cs)

Question 61

Which of the following nuclear reactions is forbidden?

A) +
→
+ 2

B) +
→

C) +
→ 2

D) n₁ + →
n +
o + 3 n₁

Question 62

A neutron star has approximately the same density as nuclear material. If a neutron star has the same mass as the Sun, 1.99 × 10³⁰ kg, what would be its radius? Use the relationship r = (1.2 fm) A^1/3 together with the mass of a neutron, 1.67 × 10⁻²⁷kg, to estimate the answer.

A) 12 km
B) 19 km
C) 13 km
D) 9.8 km

Question 63

For a sample of a given radioactive isotope, the ratio of the number of atoms of the isotope at time t to the number at time t + T_1/2 is

A) always 2.
B) dependent on how long it has been since t = 0.
C) Dependent upon what the value of T_1/2.
D) always 1/2.
E) might be any number less than 1/2.

Question 64

The binding energy per nucleon in a nucleus is

A) the same for all nuclei.
B) the greatest for the largest nuclei.
C) the greatest for the smallest nuclei.
D) the greatest for medium-sized nuclei.

Question 65

Stars are powered by nuclear fusion in their cores, which, starting with hydrogen, produce progressively heavier elements. Near the end of a star's lifetime, stellar cores produce iron by fusion. The reason this process doesn't proceed beyond iron is that

A) iron in stellar cores tends to undergo spontaneous fission.
B) iron is the most dense material in solid form.
C) iron nuclei have the greatest binding energy per nucleon.
D) iron is ferromagnetic.
E) iron is heavy.

Question 66

The burning of one gallon of gasoline releases about 2 × 10⁸ J. If each nuclear fission reaction in a nuclear power plant releases 173 MeV, what quantity of uranium-235 would produce the same energy as burning a gallon of gasoline?

A) 28 g
B) 0.28 g
C) 2.8 g
D) 0.0028 g

Question 67

Complete the following induced reaction: + → + ?

A)
B)
C)
D)

Question 68

For a selected atom in a sample of a radioactively decaying isotope, the probability that it will decay during a time interval of a specified length is

A) dependent on how long it has been since t = 0.
B) independent of when the time interval starts relative to the current time.
C) dependent upon how old the atom is.
D) fundamentally unpredictable.

Question 69

What is the radius of the nuclide ?

A) 7.4 fm
B) 5.4 fm
C) 290 fm
D) 1.8 fm

Question 70

A nuclear chain reaction is possible (for the isotopes that can participate in a chain reaction) because when each nucleus fissions, it produces

A) more neutrons than are required to induce fission in one nucleus.
B) more energy than is required to induce fission in one nucleus.
C) daughters that can also be induced to fission to produce more energy.
D) daughters that can fuse together to make more of the same isotope.

Question 71

Carbon-14 has a half-life of 5730 years. You discover a single carbon-14 nucleus in your laboratory. What is the probability that it will decay in the next 24 hours?

A) 4.9 × 10⁻⁷
B) 3.3 × 10⁻⁷
C) 4.8 × 10⁻⁷
D) It cannot be known unless the age of the nucleus is known.

Question 72

Fusion normally involves relatively light nuclei because

A) fusion produces heavier nuclei, and the binding energy per nucleon decreases with atomic number for low atomic numbers.
B) they are the most plentiful.
C) they are easier to ionize and thus to cause their nuclei to coalesce.
D) fusion produces heavier nuclei, and the binding energy per nucleon increases with atomic number for low atomic numbers.

Question 73

If each nuclear fission reaction in a nuclear power plant releases 173 MeV, what quantity of uranium-235 must be consumed each day to keep a 350 MW plant producing at capacity? Assume the power plant is 35% efficient.

A) 5.2 kg
B) 1.8 kg
C) 0.43 kg
D) 1.2 kg

Question 74

Compared to the sum of the masses of its constituents, the mass of a nucleus (other than ¹H) is

A) the same.
B) greater.
C) less.
D) could be any of the above.

Question 75

When a nucleus of a given isotope decays, it

A) cannot produce a daughter with the same mass number.
B) always produces a daughter with a lower mass number.
C) cannot produce a daughter with a lower mass number.
D) cannot produce a daughter with a higher mass number.
E) always produces a daughter with a higher mass number.

Question 76

Nuclear fuel enrichment is the process by which the concentration of what component of nuclear fuel is increased artificially?

A) Plutonium-239
B) Uranium-235
C) Deuterium
D) Uranium-238

Question 77

How many neutrons are produced in the following induced fission reaction? n₁ + → r + e + neutrons

A) 2
B) 0
C) 1
D) 3