Match List-I with List-II
| List-I | List-II |
| (A) Discovery of nucleus | (I) James Chadwick |
| (B) Discovery of neutrons | (II) Ernst Rutherford |
| (C) Discovery of radioactivity | (III) W. Pauli |
| (D) Prediction of neutrinos | (IV) Henri Becquerel |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → (A) – (II), (B) – (I), (C) – (IV), (D) – (III)
Each entry in List-I is a landmark in atomic and nuclear physics; match it with the scientist who made the discovery or prediction.
(A) Discovery of nucleus — this matches (II) Ernst Rutherford. In the alpha-particle scattering experiment (Geiger and Marsden, 1911), a few alpha particles bounced back from a gold foil, which showed that the positive charge and almost all the mass of an atom sit in a tiny nucleus.
(B) Discovery of neutrons — this matches (I) James Chadwick. In 1932 he showed that the penetrating radiation from beryllium bombarded with alpha particles consists of neutral particles with nearly the mass of a proton.
(C) Discovery of radioactivity — this matches (IV) Henri Becquerel. In 1896 he found that uranium salts blacken a wrapped photographic plate without any exposure to light.
(D) Prediction of neutrinos — this matches (III) W. Pauli. In 1930 he proposed a light neutral particle emitted in beta decay, to explain the continuous energy spectrum of beta particles while keeping energy and momentum conserved.
NCERT (2026-27):
Alpha-particle Scattering and Rutherford’s Nuclear Model of Atom – “… This is why Rutherford is credited with the discovery of the nucleus.”
Atomic Masses and Composition of Nucleus – “… Chadwick was awarded the 1935 Nobel Prize in Physics for his discovery of the neutron.”
Radioactivity – “A. H. Becquerel discovered radioactivity in 1896 purely by accident.”