THE ATOMIC NUCLEUS
The atomic nucleus consists of:
a) Protons and electrons
b) Protons and neutrons
c) Electrons and neutrons
d) Electrons and positrons
Which of the following particles is found in the atomic nucleus?
a) Electrons
b) Neutrons
c) Protonsa
d) All of the above
Isotopes are atoms that have the same number of:
a) Neutrons
b) Protons
c) Electrons
d) Nuclei
1. The atomic nucleus consists of:
a) Protons and electrons
b) Protons and neutrons
c) Electrons and neutrons
d) Electrons and positrons
2. Which of the following particles is found in the atomic nucleus?
a) Electrons
b) Neutrons
c) Protons
d) All of the above
3. Isotopes are atoms that have the same number of:
a) Neutrons
b) Protons
c) Electrons
d) Nuclei
4. Radioactivity is the spontaneous emission of:
a) Electrons
b) Protons
c) Neutrons
d) Radiation
5. Which of the following is not a type of radioactive decay?
a) Alpha decay
b) Beta decay
c) Gamma decay
d) Delta decay
6. The half-life of a radioactive substance is the time it takes for:
a) Half of the substance to decay
b) All of the substance to decay
c) A quarter of the substance to decay
d) One-tenth of the substance to decay
7. Which of the following is a conservation law in nuclear changes?
a) Conservation of mass
b) Conservation of energy
c) Conservation of charge
d) All of the above
8. The mass-energy equivalence is described by:
a) Einstein's law of relativity
b) Newton's laws of motion
c) Bohr's atomic model
d) Planck's quantum theory
9. The mass defect in a nucleus is the difference between:
a) The mass of the nucleus and the mass of its constituent nucleons
b) The mass of the nucleus and the mass of an electron
c) The mass of the nucleus and the mass of a photon
d) The mass of the nucleus and the mass of a neutron
10. Binding energy is the energy required to:
a) Break a nucleus into its constituent nucleons
b) Form a nucleus from its constituent nucleons
c) Convert a proton into a neutron
d) Create a positron-electron pair
11. Photons-induced reactions occur when:
a) Photons collide with other photons
b) Photons collide with electrons
c) Photons collide with protons
d) Photons collide with atomic nuclei
12. Deuteron-induced reactions involve collisions with:
a) Protons
b) Neutrons
c) Electrons
d) Deuterons
13. Gamma-induced reactions involve the absorption of:
a) Alpha particles
b) Beta particles
c) Gamma rays
d) X-rays
14. Nuclear fission is the process of:
a) Combining two atomic nuclei into one
b) Splitting an atomic nucleus into two or more smaller nuclei
c) Converting protons into neutrons
d) Converting neutrons into protons
15. Nuclear fusion is the process of:
a) Splitting an atomic nucleus into two or more smaller nuclei
b) Combining two atomic nuclei into one
c) Converting protons into neutrons
d) Converting neutrons into protons
16. Nuclear reactors utilize controlled nuclear reactions to:
a) Generate electricity
b) Produce chemical reactions
c) Accelerate particles
d) Create nuclear weapons
17. Nuclear fuel used in reactors is typically enriched with:
a) Neutrons
b) Protons
c) Uranium-235
d) Plutonium-239
18. Moderators in nuclear reactors are used to:
a) Slow down neutrons
b) Speed up neutrons
c) Absorb gamma rays
d) Control the temperature
19. Coolants in nuclear reactors are used to:
a) Absorb neutrons
b) Absorb gamma rays
c) Transfer heat
d) Generate electricity
20. Control materials in nuclear reactors are used to:
a) Absorb neutrons
b) Absorb gamma rays
c) Regulate the nuclear reactions
d) Cool the reactor core
21. Shielding in nuclear reactors is used to:
a) Slow down neutrons
b) Absorb gamma rays
c) Control the temperature
d) Generate electricity
22. A breeder reactor is designed to:
a) Produce more fissile material than it consumes
b) Generate electricity without fuel consumption
c) Convert protons into neutrons
d) Split atomic nuclei into smaller fragments
23. The process of converting protons into neutrons is called:
a) Fission
b) Fusion
c) Neutron capture
d) Beta decay
24. The most common isotope of hydrogen is:
a) H-1
b) H-2
c) H-3
d) H-4
25. The decay of a radioactive substance follows a:
a) Linear pattern
b) Exponential pattern
c) Parabolic pattern
d) Circular pattern
26. The number of protons in an atom determines its:
a) Atomic number
b) Atomic mass
c) Atomic radius
d) Atomic weight
27. The process of converting neutrons into protons is called:
a) Fission
b) Fusion
c) Neutron capture
d) Beta decay
28. Which of the following particles has the least mass?
a) Proton
b) Electron
c) Neutron
d) Alpha particle
29. The binding energy per nucleon is highest for:
a) Light elements
b) Heavy elements
c) Elements in the middle of the periodic table
d) Elements with odd atomic numbers
30. The decay of a radioactive substance can be influenced by:
a) Temperature
b) Pressure
c) Magnetic field
d) None of the above
31. The process of nuclear fusion powers:
a) Stars
b) Electric cars
c) Geothermal plants
d) Wind turbines
32. A control rod in a nuclear reactor is used to:
a) Absorb excess neutrons
b) Generate electricity
c) Initiate the fission chain reaction
d) Cool the reactor core
33. In a nuclear reaction, the sum of the atomic numbers:
a) Remains the same
b) Decreases
c) Increases
d) Depends on the type of reaction
34. A positron is:
a) A positively charged electron
b) A neutron with positive charge
c) An anti-particle of the proton
d) An unstable isotope of hydrogen
35. The process of converting neutrons into protons is accompanied by the emission of:
a) Alpha particles
b) Beta particles
c) Gamma rays
d) Positrons
36. The process of nuclear fission releases a large amount of:
a) Heat energy
b) Mechanical energy
c) Electrical energy
d) Chemical energy
37. The main fuel used in most commercial nuclear reactors is:
a) Uranium-235
b) Plutonium-239
c) Thorium-232
d) Hydrogen-1
38. The splitting of an atomic nucleus in nuclear fission is triggered by:
a) Neutron bombardment
b) Proton bombardment
c) Gamma ray bombardment
d) Electron bombardment
39. The process of nuclear fusion releases energy due to the:
a) Conversion of mass into energy
b) Conversion of energy into mass
c) Emission of alpha particles
d) Formation of new chemical bonds
40. The breeder reactor produces more fuel than it consumes by converting:
a) Uranium-235 into plutonium-239
b) Plutonium-239 into uranium-235
c) Neutrons into protons
d) Protons into neutrons
41. The half-life of a radioactive substance is 10 days. If you start with 100 grams, how much will remain after 30 days?
a) 12.5 grams
b) 25 grams
c) 50 grams
d) 75 grams
42. The binding energy of a nucleus is 120 MeV. If the mass defect of the nucleus is 0.02 atomic mass units (amu), what is the mass defect in kilograms?
a) 3.16 x 10^-29 kg
b) 5.31 x 10^-29 kg
c) 6.32 x 10^-29 kg
d) 8.92 x 10^-29 kg
43. A gamma ray with a frequency of 2.5 x 10^19 Hz has an energy of:
a) 1.66 x 10^-12 J
b) 3.98 x 10^-12 J
c) 6.63 x 10^-12 J
d) 9.24 x 10^-12 J
44. A nucleus with an atomic mass of 100 amu has a binding energy of 80 MeV. What is the binding energy per nucleon?
a) 0.8 MeV
b) 1.6 MeV
c) 2.0 MeV
d) 4.0 MeV
45. In a nuclear reaction, 10 neutrons and 10 protons combine to form a new nucleus. What is the atomic number of the resulting nucleus?
a) 5
b) 10
c) 15
d) 20
46. A radioactive substance has a decay constant of 0.02 per day. What is its half-life?
a) 10 days
b) 20 days
c) 30 days
d) 40 days
47. A nuclear reactor generates 100 MW of thermal power with an efficiency of 30%. What is the electrical power output of the reactor?
a) 30 MW
b) 50 MW
c) 70 MW
d) 90 MW
48. A radioactive sample decays from 1000 counts to 125 counts in 8 hours. What is the half-life of the substance?
a) 1 hour
b) 2 hours
c) 4 hours
d) 6 hours
49. A nucleus has 92 protons and 143 neutrons. What is its atomic mass number?
a) 35
b) 92
c) 143
d) 235
50. The decay constant of a radioactive substance is 0.05 per hour. What is the average lifetime of the substance?
a) 10 hours
b) 20 hours
c) 30 hours
d) 40 hours
ANSWER KEY:
1. b) Protons and neutrons
2. c) Protons
3. a) Neutrons
4. d) Radiation
5. d) Delta decay
6. a) Half of the substance to decay
7. d) All of the above
8. a) Einstein's law of relativity
9. a) The mass of the nucleus and the mass of its constituent nucleons
10. b) Form a nucleus from its constituent nucleons
11. d) Photons collide with atomic nuclei
12. d) Deuterons
13. c) Gamma rays
14. b) Splitting an atomic nucleus into two or more smaller nuclei
15. b) Combining two atomic nuclei into one
16. a) Generate electricity
17. c) Uranium-235
18. a) Slow down neutrons
19. c) Transfer heat
20. c) Regulate the nuclear reactions
21. b) Absorb gamma rays
22. a) Produce more fissile material than it consumes
23. a) Fission
24. a) H-1
25. b) Exponential pattern
26. a) Atomic number
27. b) Fusion
28. b) Electron
29. b) Heavy elements
30. d) None of the above
31. a) Stars
32. a) Absorb excess neutrons
33. a) Remains the same
34. a) A positively charged electron
35. b) Beta particles
36. a) Heat energy
37. a) Uranium-235
38. a) Neutron bombardment
39. a) Conversion of mass into energy
40. a) Uranium-235 into plutonium-239
41. a) 12.5 grams
42. a) 3.16 x 10^-29 kg
43. a) 1.66 x 10^-12 J
44. c) 2.0 MeV
45. b) 10
46. b) 20 days
47. a) 30 MW
48. c) 4 hours
49. d) 235
50. c) 30 hours
