The neutron was discovered in 1932 by which scientist?
- A.J. J. Thomson
- B.Ernest Rutherford
- C.James Chadwick
- D.Niels Bohr
Correct answer
Explanation
The correct answer is C, James Chadwick. Chadwick showed in 1932 that the radiation given off when beryllium is struck by alpha particles consists of neutral particles of about the mass of a proton, and he named them neutrons; he received the Nobel Prize in Physics for it. Option A is wrong because J. J. Thomson discovered the electron in 1897 through his cathode ray experiments. Option B is wrong because Ernest Rutherford discovered the atomic nucleus with the gold foil experiment and named the proton, and although he had predicted a neutral particle, he did not find it. Option D is wrong because Niels Bohr gave the model of the atom in which electrons occupy fixed energy levels. Fix the order for the exam: electron in 1897, nucleus and proton with Rutherford, neutron with Chadwick in 1932.
Read the full article: Inventions and Inventors: Pairs, Years and Exam PYQs
Practice Questions
View allWhat did Wilhelm Conrad Roentgen discover?
- A.Conservation of electric charge
- B.Electric bulb
- C.X-Rays
- D.Thermodynamics
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Roentgen, a German physicist, noticed in 1895 that a screen in his darkened laboratory glowed while a covered discharge tube was running, and he named the unknown radiation X-rays.
Read the full explanation →Who is called the father of immunology?
- A.Robert Koch
- B.Louis Pasteur
- C.Edward Jenner
- D.Karl Landsteiner
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In 1796 Jenner showed that material from a cowpox sore protected a boy against smallpox, the first deliberate vaccination, and the word vaccine itself comes from vacca, the Latin for cow.
Read the full explanation →Which one of the following pairs is NOT correctly matched?
- A.Vitamin A - McCollum
- B.Vitamin B - McCollum
- C.Vitamin C - Albert Szent-Gyorgyi
- D.Vitamin D - Paul Muller
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Paul Hermann Muller is remembered for showing that DDT kills insects, work for which he received a Nobel Prize in Physiology or Medicine; vitamin D is associated with Edward Mellanby, who linked its absence to rickets, and with Adolf Windaus, who worked out its chemistry.
Read the full explanation →Who is credited with the invention of the telephone?
- A.Samuel Morse
- B.Alexander Graham Bell
- C.Guglielmo Marconi
- D.Thomas Alva Edison
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Bell received the patent for the telephone in 1876 and made the first call over a wire, carrying the human voice itself rather than a code.
Read the full explanation →Dynamite, whose inventor endowed a set of international prizes, was invented by:
- A.Alfred Nobel
- B.Rudolf Diesel
- C.Michael Faraday
- D.James Watt
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The Swedish chemist Alfred Nobel patented dynamite in 1867, a safe way of handling nitroglycerine, and the fortune he made from explosives endowed the Nobel Prizes, first awarded in 1901.
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