# Final state of Hydrogen atom?

#### starrysky

A ground state hydrogen atom absorbs a photon of light having a wavelength of 92.27 nm. It then gives off a photon having a wavelength of 383.4 nm. What is the final state of the hydrogen atom? Values for physical constants can be found here.

#### topsquark

Forum Staff
A ground state hydrogen atom absorbs a photon of light having a wavelength of 92.27 nm. It then gives off a photon having a wavelength of 383.4 nm. What is the final state of the hydrogen atom? Values for physical constants can be found here.
Houston we have a problem.

The Rydberg formula says:

1/(lambda) = R ( 1/n1^2 - 1/n2^2)
where R = 1.097 x 10^7/m

For the first part n1 = 1 and (lambda) = 92.27 nm and n1 = 1. Solving this for n2 I get n2 = 9.108, so your answer would be n2 = 9.

The problem is that, for the second part, the emitted photon has a greater wavelength than the original photon. That makes the transition to a state with an energy less than the ground state, which is impossible.

Is this a problem with randomly generated numbers?

-Dan