Physics · Chemistry

Radioactivity and Nuclear Physics

519 Questions

Radioactivity and nuclear physics encompass the study of radioactive decay processes, neutron to proton ratios, and nuclear medicine. Questions cover various detection mechanisms, including scintillation counters and neutrino telescopes. These concepts are frequently tested in advanced science and civil services examinations.

Radioactive decayNuclear medicineParticle detectionNeutrino telescopesCosmic ray detection

Radioactivity and Nuclear Physics Questions

Multiple choice

What is the nature of Radon?

  1. Halogen

  2. Gas

  3. Alkali metal

  4. Non metal
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Radon is a chemical element with the symbol Rn and is a radioactive noble gas.

Multiple choice

In which of the following nuclear reactions, 8α and 6β particles have been emitted?

  1. 92U238 → 82Pb206

  2. 90Th228 → 83Bi212

  3. 92U235 → 89Ac227

  4. 92U235 → 82Pb207

  5. 92U235 → 90Th231
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

92U238 → 82Pb206 Change in mass number = 238 - 206 = 32 The mass number changes only because of α-particle emission Hence, number of α-particles emitted = 32/4 = 8 After emission of 8 α-particles, the atomic number should change by 2 x 8 = 16 Actual change in atomic number = 92 - 82 = 10 Hence, number of β-particles emitted = 16 - 10 = 6

Multiple choice

Which of the following statements about radioactive disintegration is not correct?

  1. Actinium series emits 6α and 4β particles.

  2. The end product of 4n+3 series is Pb-207.

  3. The end product of 4n+2 disintegration series is Pb-206.

  4. Neptunium series is artificial radioactive disintegration series.

  5. Starting element of 4n disintegration series is Th-232.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

4n+3 disintegration series (Actinium series): Starting element - U-235 End product - Pb-207 Emits 7α and 4β particles Natural radioactive disintegration series

Multiple choice

What is enriched Uranium?

  1. Uranium that has been exposed to extense radiation

  2. U - 235

  3. U - 238

  4. Natural Uranium which has been coated with U - 235
Reveal answer Fill a bubble to check yourself
D Correct answer
Multiple choice

Which among the following inorganic compounds is highly radioactive in nature?

  1. Zirconium(IV) chloride

  2. Zirconium carbide

  3. Zirconium silicate

  4. Chernobylite
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Chernobylite is a technogenic mineral with high (up to 10%) content of uranium as a solid solution. It is black and yellow. It was discovered in the corium produced in the Chernobyl accident, a lava-like glassy material formed in a nuclear meltdown of a reactor core. Chernobylite is highly radioactive due to its high uranium content and contamination by fission products.

Multiple choice

Which of the following compounds is used in radiation detection?

  1. Sodium iodate

  2. Sodium iodide

  3. Sodium laureth sulphate

  4. Sodium lauroamphoacetate
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Sodium iodide is a white, crystalline salt with chemical formula (NaI) used in radiation detection, treatment of iodine deficiency, and as a reactant in the Finkelstein reaction.

Multiple choice

Why is it suitable to use a beta radiation source, rather than an alpha or gamma source, to monitor the thickness of the sheet?

  1. Gamma radiation affects the properties of the sheet.

  2. The gamma signal changes in a regular way with thickness changes.

  3. The beta signal changes in a regular way with thickness changes.

  4. Too little alpha radiation is absorbed on the surface to check the thickness.

  5. One can easily protect workers from the effects of beta radiation.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Beta radiation has moderate penetration power (alpha low, gamma high) and more is stopped the thicker the material. The electronic signal from the detector varies in a regular way depending on the thickness.

Multiple choice

Consider the following statements:

  1. When radioactive uranium loses its entire radioactivity, it decays into carbon.
  2. India is an exporter of hematite, granite and bauxite.

Which of the given statements is/are incorrect?

  1. Only 1

  2. Only 2

  3. Both 1 and 2

  4. Neither 1 nor 2
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Statement 1 is incorrect. When radioactive uranium loses its entire radioactivity, it decays into lead. Statement 2 is correct. India is an exporter of hematite, granite and bauxite.