Frequency of a Photon: Chemistry

Question

Calculate the frequency (in Hz) of a photon emitted during a transition corresponding to the fourth line in the Lyman series (n_f = 1) of the hydrogen emission spectrum.

(Report your answer to three significant figures.)

Answer 1

This is very much like your previous question. 

The first line is generated when an electron falls from n=2; second line is when an electron falls from n=3 and the third line is when an electron falls from n=4 And the 4th line is for n=5. Thus, for this problem ni = 5 and nf = 1

We can use the equation 1/λ = R(1/nf2 - 1/ni2) where R is the Rydberg constant = 1.097x107 m-1. Plug in the values for nf and ni and solve for λ. Then from the calculated wavelength, find the corresponging frequency using c = λν where c is 3x10⁸ m/sec (speed of light).