Question

Artificial radioactivity was discovered by:
A. Rontgen
B. Becquerel
C. Marie Curie
D. Irene Joliot Curie

Answer 1

Hint: Radioactivity is a natural process in which an unstable nucleus loses energy in the form of radiation to form a new nucleus, buy artificial radio-activity is the man-made radioactivity where radiation is used to induce radioactivity in a previously stable material.

 Complete step by step answer:
-Rontgen - Rontgen was a physicist who detected and invented some rays of electromagnetic radiation which falls in certain wavelengths which are called . Since he was involved in x-ray discovery, he did not discover artificial radio-activity. Hence, it is not the correct answer.
-Becquerel - Becquerel is the derived unit of radioactivity in the SI unit system. It is named after French Scientist Antoine Henri Becquerel after he studied , and observed that uranium is a radioactive element. Since, it is not related to artificial radioactivity, so, it is a wrong answer.
-Marie Curie - Marie Curie was a chemist and physicist who studied radiation and discovered the elements Polonium, and Radium. She was not involved in the discovery of artificial radioactivity. Hence, Marie Curie is not the correct answer.
-Irene Joliot Curie - She was the daughter of Marie Curie, and she was awarded the Nobel prize for discovering artificial radioactivity. She discovered that alpha-particle bombardment of aluminium elements produces an intermediate unstable isotope which is phosphorus.
Hence, option (d) is the correct answer. Irene Joliot Curie discovered artificial radio-activity.

Note: Artificial radioactivity, also called induced radioactivity, makes a radioactive isotope by capturing neutrons. Addition of neutrons to a nuclide results in an increase in the number of isotopes by , while keeping the same atomic number.