Question 1

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

Accepted Answer

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

Question 2

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

Accepted Answer

A)  2.4 × 10-20 
B)  1.5 × 10-7 
C)  1.8 × 10-16 
D)  6.1 × 10-15 
E)  None of these choices are correct. 
A)  2.4 × 10-20 
B)  1.5 × 10-7 
C)  1.8 × 10-16 
D)  6.1 × 10-15 
E)  None of these choices are correct.

Question 3

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

Accepted Answer

A)  positron decay. 
B)  α decay. 
C)    decay. 
D)  electron capture. 
E)  β decay. 
A)  positron decay. 
B)  α decay. 
C)    decay. 
D)  electron capture. 
E)  β decay.

Question 4

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

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 5

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

Accepted Answer

A)  α decay. 
B)  β decay. 
C)    decay. 
D)  positron decay. 
E)  electron capture. 
A)  α decay. 
B)  β decay. 
C)    decay. 
D)  positron decay. 
E)  electron capture.

Question 6

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

Accepted Answer

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

Question 7

The isotope   is unstable. This is predictable because

Accepted Answer

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. 
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 8

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

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 9

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

Accepted Answer

A)  0.003232 Ci/g 
B)  0.0115 Ci/g 
C)  0.309 Ci/g 
D)  3.23 Ci/g 
E)  None of these choices are correct. 
A)  0.003232 Ci/g 
B)  0.0115 Ci/g 
C)  0.309 Ci/g 
D)  3.23 Ci/g 
E)  None of these choices are correct.

Question 10

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

Accepted Answer

A)  α decay. 
B)  β decay. 
C)  positron decay. 
D)  electron capture. 
E)    decay. 
A)  α decay. 
B)  β decay. 
C)  positron decay. 
D)  electron capture. 
E)    decay.

Question 11

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

Accepted Answer

A)  2.1 × 10-19 
B)  1.2 × 10-17 
C)  2.2 × 10-9 
D)  1.2 × 10-9 
E)  None of these choices are correct. 
A)  2.1 × 10-19 
B)  1.2 × 10-17 
C)  2.2 × 10-9 
D)  1.2 × 10-9 
E)  None of these choices are correct.

Question 12

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

Accepted Answer

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

Question 13

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.

Accepted Answer

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

Question 14

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?

Accepted Answer

A)  13.2 kJ 
B)  1.32 × 104 kJ 
C)  1.32 × 106 kJ 
D)  1.32 × 109 kJ 
E)  None of these choices are correct. 
A)  13.2 kJ 
B)  1.32 × 104 kJ 
C)  1.32 × 106 kJ 
D)  1.32 × 109 kJ 
E)  None of these choices are correct.

Question 15

Identify the missing species in the following nuclear transmutation.

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 16

Gamma-rays and X-rays interact with matter, causing

Accepted Answer

A)  formation of ions, but no free radicals. 
B)  formation of free radicals, but no ions. 
C)  nuclear transmutation reactions. 
D)  formation of ions and free radicals. 
E)  formation of ions and nuclear transmutation reactions. 
A)  formation of ions, but no free radicals. 
B)  formation of free radicals, but no ions. 
C)  nuclear transmutation reactions. 
D)  formation of ions and free radicals. 
E)  formation of ions and nuclear transmutation reactions.

Question 17

The radioisotope   will decay through

Accepted Answer

A)  α decay. 
B)  β decay. 
C)  decay. 
D)  electron capture. 
E)  spontaneous fission. 
A)  α decay. 
B)  β decay. 
C)  decay. 
D)  electron capture. 
E)  spontaneous fission.

Question 18

Select the nuclide that completes the following nuclear reaction.

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 19

Palladium-107 undergoes β decay (t1/2 = 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?

Accepted Answer

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 
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 20

Which of the following isotopes is definitely unstable?

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Exam 24: Nuclear Reactions and Their Applications

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

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

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

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

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

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

The isotope is unstable. This is predictable because

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

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

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

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

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

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.

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?

Identify the missing species in the following nuclear transmutation.

Gamma-rays and X-rays interact with matter, causing

The radioisotope will decay through

Select the nuclide that completes the following nuclear reaction.

Palladium-107 undergoes β decay (t1/2 = 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?

Which of the following isotopes is definitely unstable?

Keys to Studying Chemistry Definitions, Units, and Problem Solving

The Components of Matter

Stoichiometry of Formulas and Equations

Three Major Classes of Chemical Reactions

Gases and the Kinetic-Molecular Theory

Thermochemistry Energy Flow and Chemical Change

Quantum Theory and Atomic Structure

Electron Configuration and Chemical Periodicity

Models of Chemical Bonding

The Shapes of Molecules

Theories of Covalent Bonding

Intermolecular Forces Liquids, Solids, and Phase Changes

The Properties of Mixtures Solutions and Colloids

Periodic Patterns in the Main-Group Elements

Organic Compounds and the Atomic Properties of Carbon

Kinetics Rates and Mechanisms of Chemical Reactions

Equilibrium the Extent of Chemical Reactions

Acid-Base Equilibria

Ionic Equilibria in Aqueous Systems

Thermodynamics Entropy, Free Energy, and Reaction Direction

Electrochemistry Chemical Change and Electrical Work

The Elements in Nature and Industry

Transition Elements and Their Coordination Compounds

Filters

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

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

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

Palladium-107 undergoes β 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?