Deck 24: Nuclear Reactions and Their Applications

Question 1

Select the nuclide that completes the following nuclear reaction.

A)
B)
C)
D)
E)

Answer 1

Question 2

Select the nuclide that completes the following nuclear reaction.

A)
B)
C)
D)
E)

Answer 2

Question 3

Select the nuclide that completes the following nuclear reaction.

A)
B)
C)
D)
E)

Answer 3

Question 4

Which one of the following is an incorrect representation of the indicated particle or nucleus?

A) positron:
B) neutron:
C) helium-3:
D) alpha particle:
E) proton:

Question 5

The radioisotope will decay through

A) . decay.
B) . decay.
C) positron decay.
D) electron capture.
E) . decay.

Question 6

Which one of the following equations correctly represents positron decay of ?

A)
B)
C)
D)
E)

Question 7

The radioisotope will decay through

A) . decay.
B) . decay.
C) . decay.
D) electron capture.
E) spontaneous fission.

Question 8

An isotope with a low value of N/Z will generally decay through

A) . decay.
B) . decay.
C) . decay.
D) electron capture.
E) spontaneous fission.

Question 9

Select the nuclide that completes the following nuclear reaction.

A)
B)
C)
D)
E)

Question 10

Select the nuclide that completes the following nuclear reaction.

A)
B)
C)
D)
E) none of the above

Question 11

Select the nuclide that completes the following nuclear reaction.

A)
B)
C)
D)
E) none of the above

Question 12

Which one of the following descriptions relating to nuclear reactions is correct?

A) The ratio of neutrons to protons remains constant.
B) The number of protons plus neutrons remains constant.
C) The number of electron remains constant.
D) The total charge changes.
E) The total number of nucleons changes.

Question 13

Select the nuclide that completes the following nuclear reaction.

A)
B)
C)
D)
E)

Question 14

Which one of the following equations correctly represents alpha decay of ?

A)
B)
C)
D)
E)

Question 15

Who discovered radioactivity?

A) Geiger
B) Curie
C) Roentgen
D) Becquerel
E) Rutherford

Question 16

Which of the following types of radioactive decay does not produce new element?

A) gamma emission
B) electron capture
C) beta emission
D) alpha emission
E) double beta emission

Question 17

Which one of the following is a subatomic particle closely related to the positron?

A) proton
B) electron
C) negatron
D) neutron
E) neutrino

Question 18

Select the nuclide that completes the following nuclear reaction.

A)
B)
C)
D)
E)

Question 19

An isotope with a high value of N/Z will tend to decay through

A) . decay.
B) . decay.
C) positron decay.
D) electron capture.
E) . decay.

Question 20

Which one of the following equations correctly represents electron capture by the nucleus?

A)
B)
C)
D)
E)

Question 21

What is the specific activity (in Ci/g) of an isotope if 3.56 mg emits 4.26 × 10⁸  particles per second?

A) 0.003232 Ci/g
B) 0.0115 Ci/g
C) 0.309 Ci/g
D) 3.23 Ci/g
E) none of the above

Question 22

Which of the following isotopes is most likely to be unstable?

A)
B)
C)
D)
E)

Question 23

The isotopes are all stable, while is radioactive. The mode of decay for is most likely to be

A) positron decay.
B) . decay.
C) . decay.
D) electron capture.
E) . decay.

Question 24

Which of the following series of radioactive decays would convert Pa-234 to Ra-226?

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

Question 25

A certain isotope has a specific activity of 7.29 × 10^-4 Ci/g. How many  particles will a 75.0 mg sample emit in one hour?

A) 9.99 × 10⁴
B) 2.02 × 10⁶
C) 7.28 × 10⁹
D) 1.29 × 10¹²
E) none of the above

Question 26

A scintillation counter

A) measures the signal coming from an ionized gas.
B) measures light emissions from excited atoms.
C) depends on an avalanche of electrons generated as a particle moves through a tube of argon gas.
D) detects high energy radiation better than low energy radiation.
E) detects an electric current in a gas.

Question 27

So-called "magic numbers" of particles are thought to convey extra stability to certain nuclei. These magic numbers refer to which of the following particles?

A) protons only
B) electrons only
C) positrons only
D) neutrons only
E) protons and neutrons

Question 28

Which of the following isotopes is definitely unstable?

A)
B)
C)
D)
E)

Question 29

The nuclide Pb-210 undergoes three successive decays (beta, alpha, and beta, respectively) to form a stable nuclide. What are the three nuclides which form from Pb-210 in this decay series?

A) Tl-210, Au-206, Pt-206
B) Bi-210, Tl-206, Pb-206
C) Pb-209, Hg-205, Hg-204
D) Bi-210, Pb-206, Bi-206
E) none of the above

Question 30

An isotope with Z > 83, which lies close to the band of stability, will generally decay through

A) . decay.
B) . decay.
C) . decay.
D) positron decay.
E) electron capture.

Question 31

The isotope is unstable. This is predictable because

A) N/Z  1.
B) N/Z is relatively low and Z < 20.
C) N/Z is relatively large and Z < 20.
D) Z is small.
E) N is large.

Question 32

Detection of radiation by a Geiger-Müller counter depends on

A) the emission of a photon from an excited atom.
B) the ability of an ionized gas to carry an electrical current.
C) the emission of a photon of light by the radioactive particle.
D) the ability of a photomultiplier tube to amplify the electrical signal from a phosphor.
E) the detection of the sound made by decay particles.

Question 33

The radioisotope will decay through

A) . decay.
B) . decay.
C) . decay.
D) positron decay.
E) electron capture.

Question 34

The radiochemist, Will I. Glow, studied thorium-232 and found that 2.82 × 10^-7 moles emitted 8.42 × 10⁶  particles in one year. What is the decay constant for thorium-232?

A) 3.35 × 10^-14 yr^-1
B) 4.96 × 10^-11 yr^-1
C) 1.40 × 10¹⁰ yr^-1
D) 2.99 × 10¹³ yr^-1
E) none of the above

Question 35

Which one of the following nuclei has a magic number of neutrons and/or protons?

A)
B)
C)
D)
E)

Question 36

The isotope is unstable. This is predictable because

A) the number of neutrons is too large in relation to the number of protons.
B) the number of neutrons is too small in relation to the number of protons.
C) the atomic number is too large.
D) the mass number is too large.
E) Sc isotopes are all unstable.

Question 37

The isotopes of promethium, and are unstable, and lie on opposite sides of the "line of stability". Which of the following combinations is most likely to represent the type of decay for these isotopes?

A) promethium-144,  decay; promethium-134, positron decay
B) promethium-144, positron decay; promethium-134,  decay
C) promethium-144, positron decay; promethium-134, electron capture
D) promethium-144, electron capture; promethium-134, positron decay
E) promethium-144,  decay; promethium-134,  decay

Question 38

The isotopes and are all stable, while is radioactive. The mode of decay for is most likely to be

A) positron decay.
B) alpha decay.
C) beta decay.
D) gamma decay.
E) fission.

Question 39

Which of the following isotopes is most likely to be unstable?

A)
B)
C)
D)
E)

Question 40

Which of the following isotopes is most likely to be unstable?

A)
B)
C)
D)
E)

Question 41

All the disintegrations of a sample of an unknown nuclide weighing 4.6 × 10^-2 g were counted. In the first half-life of the sample, the total number of disintegrations counted was 4.3 × 10²⁰. What is the atomic weight of the unknown element?

A) 32 amu
B) 16 amu
C) 8 amu
D) 4 amu
E) none of the above

Question 42

The isotope has a half-life of 21 hours. If a sample initially contains exactly 10000 atoms of , approximately how many of these atoms will remain after one week?

A) 1250
B) 78
C) 39
D) 0
E) none of the above

Question 43

Palladium-107 undergoes  decay (t_1/2 = 6.5 × 10⁵ yr) to form silver-107. How long will it take for 0.150 mol of silver-107 to form from 1.25 mol of palladium-107?

A) 2.0 × 10⁷ y
B) 1.4 × 10⁷ y
C) 1.2 × 10⁶ y
D) 8.3 × 10⁵ y
E) 1.2 × 10⁵ y

Question 44

A pure sample of tritium, ³H, was prepared and sealed in a container for a number of years. Tritium undergoes  decay with a half-life of 12.32 years. How long has the container been sealed if analysis of the contents shows there are 5.25 mol of ³H and 6.35 mol of ³He present?

A) 2.34 y
B) 3.38 y
C) 9.77 y
D) 14.1 y
E) 25.6 y

Question 45

Cesium-134 is a  emitter with a half-life of 2.0 years. How much of a 2.50-g sample of cesium-134 will remain after 10 years?

A) 0.0024 g
B) 0.078 g
C) 0.25 g
D) 0.50 g
E) none of the above

Question 46

A 9.52 × 10^-5 mol sample of rubidium-86 emits 8.87 × 10¹⁶  particles in one hour. What is the half-life of rubidium-86?

A) 2.23 × 10^-3 h
B) 1.55 × 10^-3 h
C) 448 h
D) 645 h
E) none of the above

Question 47

A 30.0-kg child receives 2.65 × 10⁷  particles, each with an energy of 4.60 × 10^-13 J. If the RBE = 0.78, how many millirem did the child receive?

A) 3.2 × 10^-7
B) 5.2 × 10^-7
C) 5.2 × 10^-4
D) 3.2 × 10^-2
E) none of the above

Question 48

An 85-kg person exposed to barium-141 receives 2.5 × 10⁵  particles, each with an energy of 5.2 × 10^-13 J. How many rads does the person receive?

A) 2.4 × 10^-20
B) 1.5 × 10^-7
C) 1.8 × 10^-16
D) 6.1 × 10^-15
E) none of the above

Question 49

In living organisms, C-14 atoms disintegrate at a rate of 15.3 atoms per minute per gram of carbon. A charcoal sample from an archaeological site has a C-14 disintegration rate of 9.16 atoms per minute per gram of carbon. Estimate the age of this sample. The half-life of C-14 is 5730 years.

A) 3170 years
B) 3430 years
C) 4020 years
D) 4790 years
E) 6750 years

Question 50

Iodine-131, t_1/2 = 8.0 days, is used in diagnosis and treatment of thyroid gland diseases. If a laboratory sample of iodine-131 initially emits 9.95 × 10¹⁸  particles per day, how long will it take for the activity to drop to 6.22 × 10¹⁷  particles per day?

A) 2.0 days
B) 16 days
C) 32 days
D) 128 days
E) none of the above

Question 51

A 7.85 × 10^-5 mol sample of copper-61 emits 1.47 × 10¹⁹ positrons in 90.0 minutes. What is the decay constant for copper-61?

A) 0.00230 h^-1
B) 0.00346 h^-1
C) 0.207 h^-1
D) 0.311 h^-1
E) none of the above

Question 52

Identify the missing species in the following nuclear transmutation.

A)
B)
C)
D)
E)

Question 53

A 55-kg person exposed to thorium-234 receives 7.5 × 10⁴  particles, each with an energy of 1.6 × 10^-14 J. How many rads does the person receive?

A) 2.1 × 10^-19
B) 1.2 × 10^-17
C) 2.2 × 10^-9
D) 1.2 × 10^-9
E) none of the above

Question 54

A patient's thyroid gland is to be exposed to an average of 5.5 Ci for 16 days as an ingested sample of iodine-131 decays. If the energy of the  radiation is 9.7 × 10^-14 J and the mass of the thyroid is 32.0 g, what is the dose received by the patient?

A) 0.027 rads
B) 1.2 rads
C) 37 rads
D) 85 rads
E) none of the above

Question 55

A N-14 nucleus is hit by a particle, forming a C-14 nucleus and a proton as the only products. Identify the type of particle which struck the N-14 nucleus.

A) alpha
B) proton
C) electron
D) neutron
E) deuterium

Question 56

The isotope has a half-life of 7.5 seconds. If a sample contains 144 atoms of , approximately how many such atoms were there present 30 seconds earlier?

A) 576
B) 1152
C) 2304
D) 4320
E) 4.30 × 10⁸

Question 57

Identify the missing species in the following nuclear transmutation.

A) 2
B) 3
C)
D)
E)

Question 58

Identify the missing species in the following nuclear transmutation.

A)
B)
C)
D)
E) none of the above

Question 59

Assuming that no other particles are produced, which of the following particles could be used to bombard nitrogen-14 in order to make fluorine-18?

A) alpha particle
B) beta particle
C) neutron
D) proton
E) positron

Question 60

Identify the missing species in the following nuclear transmutation.

A)
B)
C)
D)
E)

Question 61

Sodium-21 will emit positrons each having an energy of 4.0 × 10^-13 J. What is this energy in MeV?

A) 4.0 × 10^-7 MeV
B) 2.5 MeV
C) 40 MeV
D) 2.5 × 10⁶ MeV
E) none of the above

Question 62

It is believed that two carbon-12 nuclei can react in the core of a supergiant star to form sodium-23 and hydrogen-1. Calculate the energy released from this reaction for each mole of hydrogen formed. The masses of carbon-12, sodium-23, and hydrogen-1 are 12.0000 amu, 22.989767 amu, and 1.007825, respectively.

A) 2.16 × 10¹⁴ kJ
B) 2.16 × 10¹¹ kJ
C) 2.16 × 10⁸ kJ
D) 2.16 × 10⁵ kJ
E) none of the above

Question 63

Write a complete, balanced equation to represent the formation of manganese-55 by the beta decay of another nuclide.

Question 64

A bottle of vintage red wine has lost its label. The concentration of tritium ( ) in the wine is 0.34 times that found in freshly bottled wines. If the half-life of tritium is 12.3 years, estimate the time elapsed since the wine was bottled.

Question 65

Carbon-14 will emit a  particle with an energy of 0.1565 MeV. What is this energy in joules?

A) 1.0 × 10^-24 J
B) 2.5 × 10^-20 J
C) 1.0 × 10^-18 J
D) 2.5 × 10^-14 J
E) none of the above

Question 66

Exposure to 10 nCi for 10 minutes is more hazardous for a child than for an adult because

A) the child's cells are dividing more rapidly than the adult's and are, therefore, more susceptible to the radiation.
B) the child's smaller body size makes the effective dose larger for the child than for the adult.
C) the child's immune system is not developed well enough to resist damage.
D) the child's skin is not as thick as an adult's and cannot block as much radiation.
E) None of the above reasons is correct.

Question 67

Explain how the number of protons and neutrons in a radioactive nucleus can be used to predict its probable mode of decay. Illustrate your answer with a schematic graph, properly labeled, showing stable nuclides (nuclei) in relation to number of protons and neutrons.

Question 68

Calcium-39 undergoes positron decay. Each positron carries 5.49 MeV of energy. How much energy will be emitted when 0.0025 mol of calcium-39 decays?

A) 13.2 kJ
B) 1.32 × 10⁴ kJ
C) 1.32 × 10⁶ kJ
D) 1.32 × 10⁹ kJ
E) none of the above

Question 69

Which of the following materials is put into a nuclear reactor to slow the chain reaction?

A) heavy water
B) moderators
C) control rods
D) reflectors
E) chlorine

Question 70

Briefly, explain the relationship between the rad and the rem as units of radiation dosage.

Question 71

Fill in missing sub- and superscripts for all particles to complete the following equation for positron decay.

Question 72

Write a complete, balanced equation to represent the electron capture decay of argon-37.

Question 73

Write a complete, balanced equation to represent the beta decay of thallium-207.

Question 74

Which one of the following elements is formed largely in supernova explosions?

A) H
B) He
C) Mg
D) Fe
E) U

Question 75

Bombardment of uranium-238 nuclei by carbon-12 nuclei produces californium-246 and neutrons. Write a complete, balanced equation for this nuclear process.

Question 76

Calculate to four significant figures
a. the mass defect in kg, and
b. the energy released in kJ/mol, when a neutron decays to produce a proton and an electron. The neutron, proton, and electron masses are 1.67493 × 10^-27 kg, 1.67262 × 10^-27 kg and 9.10939 × 10^-31 kg, respectively.

Question 77

Fill in missing sub- and superscripts for all particles to complete the following equation for alpha decay.

Question 78

Fill in missing sub- and superscripts for all particles to complete the following equation for beta decay.

Question 79

When an electron and its anti-particle, a positron, collide, they annihilate each other. Calculate the energy released in this process, in J. (The positron mass is the same as the electron mass, namely 9.11 × 10^-31 kg.)

Question 80

Write a complete, balanced equation to represent the alpha decay of radon-210.