# Physics307L:People/Josey/Balmer and Rydberg

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## Balmer Series

For this experiment, my lab partner, Kirstin, and I observed and measured the spectrum lines from the Balmer series for both hydrogen and deuterium. The Balmer series is a specific series of spectral lines that result form the moving of electrons from a higher energy state to the n=2 energy state in hydrogen. When this occurs, the electron releases a photon with a very specific energy that can be determined by the following formula:

Where **λ** is the wavelength of the light, **R** is the Rydberg constant, and both **n** and **m** are principle quantum numbers that represent the original state, **m**, and the final state, **n**, of the electron. By measuring the wavelengths of the spectral lines and solving for the above equation, we determined that the Rydberg constant for hydrogen is 1.0962 (9) * 10^{7} m^{-1}, and 1.0975 (6) * 10^{7} m^{-1} for deuterium. We were then able to compare this to the accepted values by calculating the Rydberg constant as a function of the mass of the nucleus:

where **R** is given by:

This gives values of:

for hydrogen and deuterium. Comparing our measured results to the accepted values, we found that we were less than 0.1% off of the accepted value for the constant, leading us to conclude that we were successful in our experiment.

^{SJK 03:20, 21 December 2010 (EST)}