The scientist who proposed the nuclear model of the atom was:
A. Niels Bohr
B. Ernest Rutherford
C. John Dalton
D. J.J. Thomson
Answer: Option B
Solution (By JKExamLibrary)
Rutherford's gold foil experiment (1911) showed that most of the atom is empty space with a dense positively charged nucleus. Thomson proposed the plum pudding model; Bohr gave quantized orbits; Dalton gave solid sphere model.
Explanation:
An alpha particle (α) consists of 2 protons and 2 neutrons, which is the same as a helium-4 nucleus (²⁴He²⁺). It has a +2 charge. Beta particles are electrons (β⁻) or positrons (β⁺). Gamma rays are electromagnetic waves with no mass or charge. Alpha particles have low penetration power and are stopped by a sheet of paper or skin. Rutherford used alpha particles in his scattering experiment.
Explanation:
J.J. Thomson discovered the electron in 1897 using a cathode ray tube. He showed that cathode rays were composed of negatively charged particles (electrons) that were much lighter than atoms and were a fundamental part of all matter, leading to his plum pudding model.
Explanation:
Hydrogen fuel cells combine H₂ and O₂ to produce electricity, heat, and water. It is a clean energy source. Coal, diesel, kerosene are conventional fuels burned in engines.
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