question_answer

An excited He+ ion emits two photons in succession, with wavelengths 108.5 nm and 30.4 nm, in making a transition to ground state. The quantum number n, corresponding to its initial excited state is (for photon of wavelength energy   [JEE Main Held on 12-4-2019 Morning]

A) n = 5

B) n = 4

C) n = 6

D) n = 7

Correct Answer: A

Solution :

[a]