# Electronic transition; Emission Spectra

Gold Member

## Homework Statement

A photon emitted during an electronic transition in a hydrogen atom has a wavelength of 486.2
nm. From what initial energy level (ni) did the electron transition?

## Homework Equations

Energy = hc/wavelength (h = Planck's constant; c is speed of light; and wavelength is 486.2 nm or 486.2 x 10^-9 meters).

Energy = Rydberg's constant(1/n-final^2 - 1/n-initial^2)

## The Attempt at a Solution

I calculated the energy but I I can't solve for two variables at once in one equation. How am I supposed to find the initial energy level when I have the final energy level?