MCQs on Radioactivity

MCQs on Radioactivity

Q1: The neutral atoms of all isotopes of the same element contain the same number of __________.

1. neutrons only.
2. Electrons
3. Mass numbers
4. Masses

Answer: (b) Electrons

Q2: The atomic number is not changed by which type of radioactive decay?

1. Beta
2. Gamma
3. Alpha
4. The atomic number is affected by all forms of radioactive decay

Answer: (b) Gamma

Q3: Isotopes of an element have a different number of

1. Proton
2. Neutron
3. Electron
4. atom

Answer: (b) Neutron

Q4: Three types of radioactive elements are emitted when unstable nuclei undergo radioactive decay. Which of the following is not one of them

1. Beta
2. Gamma
3. Alpha
4. delta

Answer: (d) delta

Q5: A nuclear fission reaction becoming self-sustaining depends on

1. electrons
2. Neutrons
3. Energy
4. Protons

Answer: (b) Neutrons

Q6: Helium nuclei particles are called

1. Gamma particles
2. Beta particles
3. Alpha particles
4.  No particles that are helium nuclei

Answer: (c) alpha particles

Q7: When two atomic nuclei combine it is called as

1. Chain reaction
2. Nuclear fusion
3. Nuclear decay
4. Nuclear fission

Answer: (b) Nuclear fusion

Q8: The number of protons or atomic number is reduced to 2 by which form of radioactive decay?

1. Beta-decay
2. Gamma decay
3. Alpha decay
4. None of the above

Answer: (c) Alpha decay

Q9: Which statement is true for all three types of radioactive emission?

1. They are deflected by electric fields
2. They ionise gases
3. They are completely absorbed by a thin aluminium sheet
4. They emit light

Answer: (b) They ionise gases

Q10: A nuclide of the element plutonium ₉₄ Pu ²⁴². What is the number of neutrons in its nucleus?

1. 242
2. 336
3. 148
4. 94

Answer: (c) 148