In which of the following systems will the wavelength corresponding to n = 2 to n = 1 be minimum?

We know from Rydberg's equation, the wavelength λ of emission spectrum when electrons move from n₂ energy level to n₁ energy level, is given by,




Now, here n₁=1 and n₂=2 are fixed. So wavelength is inversely proportional to


Among the options, lithium ion has the highest atomic number, Z=3.


Hence, option (d) is the correct answer.

1