Question

6. Electron de-excited from 4th level to 2nd level in
He ion and emitted radiations have wavelength 'lambda'
Same wavelength will be obtained when electron is
de-excited from
(1) 4th level to 1st level in H
(2) 6th level to 3rd level in Li2+
(3) 8th level to 4th level in Be3+
4) Both (2) & (3)​

Answer 1

The answer is (3) option.

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