# Rydberg's Equation

1. May 10, 2005

### scorpa

Hello everyone,

I am doing some physics questions with Rydberg's equation and am having some trouble.

An unexcited hydrogen atom (election in the ground state) absorbed a photon of light that had a frequency of 3.09 x 10^15 Hz. Through what transition did the election in this atom undergo?

What I did so far was convert the frequency into wavelength with was 9.7 x 10^-8m. and I know Rydberg's constant is 1.10 x 10^7, but I end up with two variables n variables. I am not quite sure where to go with this unfortunately.

Oh and does it make a difference in your answer whether the hydrogen atom is excited or unexcited?

Thanks in advance for the help!

2. May 11, 2005

### quasar987

I don't think this is a Rydberg problem. The electron's energy in the ground state is -13.6 eV, and the frequency of a photon is related to the energy it carries through

$$E=hf$$

where h is Planck's konstant. If you are told that the photon is completely absorbed by the elektron, then according to the principle of conservation of energy, it means that the electron's has absorbed all of the photon's energy. You need to find the elektron's new energy and what state (n=?) does that corespond to?