In this experiment, my lab partner Ryan and I calculated the Rydberg constant by measuring the Balmer series spectral lines of Hydrogen and Deuterium using a spectrometer and following Professor Gold's manual.
We measured wavelengths for 4 different spectral line colors 5 times using two different gas bulbs, Hydrogen and Deuterium. For Hydrogen I calculated:
For Deuterium I calculated:
These can be compared to the accepted value from wikipedia:
The Rydberg constant for Hydrogen was 21 SEM's away from the accepted value, and the one for Deuterium was 24 SEM's away.SJK 16:51, 18 December 2009 (EST)
Though my calculated Rydberg constants were too far from the accepted value to attribute this to random error, and there had to be some systematic error, I suspect I underestimated my error. Nevertheless my systematic error could include one of the following possibilities:
- Mis-calibration of the spectrometer: It is possible that in the process of aligning the spectrometer to the spectral lines from a Mercury source, we made an error (tightened the screw which turned the crystal or misread the dial)
- Gear Back lash (although we were careful to only measure values turning the gear one direction)
- Too large of a slit opening: The slit opens from one side, rather then evenly on both sides, so this may have skewed our data to one direction.