Question

Which of the following transitions represent the emission of a photon with the largest energy?

A) n = 3 to n = 1

B) n = 2 to n = 5

C) n = 1 to n = 4

D) n = 6 to n = 3

E) n = 2 to n = 1

Answer 1

Ans: (D).

Reason: Emission is possible only when electron gets transformed from higher orbit to the lower one that is from outer to inner. And absorption is when electron gets switched from inner to outer.
So 3 to 1, 6 to 3 and 2 to 1 transition leads to emission.
Larger the energy difference between orbits, then larger the frequency and shorter the wavelength.

Energy difference will be more in 6 to 3, less in 3 to 1 and still less in 2 to 1
So emission of highest frequency is possible for 6 to 3 transmission.