The difference in the frequencies of series limit of Lyman series and Balmer series is equal to the frequency of the first line of the Lyman series. Explain.

Question

Philoid · Accepted Answer

We know from Rydberg’s equation for a hydrogen atom (Z=1) the wavelength λ of emission spectrum, when electrons move from n₂ energy level to n₁ energy level, is given by,

For the difference in the series limit (last line) of Lyman series and Balmer series.

This is because n₁=1 when we are considering Lyman Series and n₁=2 when we are considering Balmer Series.

For the first line of Lyman Series,

Thus, we can see in both cases the value of 1/λ is same. So frequency (c/λ, c=speed of light=constant) will also be same for both cases.