Question

Consider an electron transition from n = 2 to n = 4 of a hydrogen atom.

What wavelength of light will the hydrogen atom absorb or emit in this electron transition?

Answer 1

The required formula for doing so is

Here λ= wavelength, Rh = Rhydberg constant n1 is the the no. of orbital the electron transitioned from and n2 is the no. of orbital the electron transitioned to (ignore the z^2 as the atom in itself isn't mentioned so we assume that it is the electron of a hydrogen atom, btw z means atomic number)

So input n1 = 2, n2 = 4, Rh = 10 973 731.6 m^(-1)

you'll find the value of wavelength by inversing the answer you get from this equation directly. I don't have my calculator with me rn so can't show exact values :(