Question

Match List - I (Experiment performed) with List-II (Phenomena discovered/ associated) and select the correct option from the options given below the lists :

List I	List II
(a) Davisson and Germer Experiment	(i) Wave nature of electrons
(b) Millikan's oil drop experiment	(ii) Charge of an electron
(c) Rutherford experiment	(iii) Quantization of energy levels
(d) Franck - Hertz experiment	(iv) Existence of the nucleus

Answer 1

Hint Davisson and Germer's experiment proved that electrons produced an interference pattern. Millikan’s oil drop experiment studied the behavior of charged oil drops in an electric field. In his experiment, Rutherford bombarded a gold foil with alpha particles which have a positive charge to observe their interaction with the gold atoms.

Complete step by step answer
Millikan’s oil drop experiment measured the charge of an electron. Before his experiment, the electron was not confirmed to exist as a charged particle. So, (b)-(ii)
Davisson and Germer's experiment proved the wave nature of electrons by bombarding a metal target with electrons and measuring the angular distribution of reflected electrons. It was found that the electrons were deflected more strongly at some angles than the other which corresponded to an interference pattern associated with wave-like behavior. So (a)-(i)
Rutherford experiment proved the presence of a nucleus in an atom by sending charged particles on a gold foil sheet and measuring the number of alpha particles that were deflected in the complete opposite direction because of the positive nuclear charge. So (c)-(iv)
The Franck – Hertz experiment was the first experiment that confirmed the presence of discrete excited states by bombarding mercury with electrons of varying energy. So (d)-(iii)

Note
To answer such questions, we must be aware of various experiments done for the advancement of modern Physics. Also, we must be careful in not mixing the Davisson and Germer experiment with Franck – Hertz experiment since the former proved the wave nature of electrons while the latter proved the quantization of energy levels using electrons.