Physics307L:People/Carrillo/Balmer Series

Balmer Series Lab Summary

• Please note that Ginny was my lab partner for this lab.

Purpose

The purpose of this lab was to learn how to measure the spectra lines of hydrogen and deuterium and compare them to the current accepted values. We observed them through a spectroscope. In theory, excited electrons emit photons of wavelengths that are equivalent to the energy of the excited electrons. The electrons were excited by using electrical simulation. With our data we were able to measure the Rydberg constant R. The following equation is as follows.

[math]\displaystyle{ \frac{1}{\lambda }=R(\frac{1}{m^2}-\frac{1}{n^2}) }[/math]

[math]\displaystyle{ m=1,2,3,...\,\! }[/math]

[math]\displaystyle{ n=2,3,4,5,...\,\! }[/math]

[math]\displaystyle{ n\gt m\,\! }[/math]

Calculations and Analysis

• As you can see from my lab notebook, the calculated Rydberg constants for Hydrogen and Deuterium are listed below.

[math]\displaystyle{ R_{Hydrogen,average}\approx1.0989562\pm 0.008\times10^7 m^{-1}\,\! }[/math]

[math]\displaystyle{ R_{Deuterium,average}\approx1.1077221\pm 0.007\times10^7 m^{-1}\,\! }[/math]

Error

For more information about our error please refer to the "error" section in my Balmer Series Lab Notebook.

• Below are the calculated percent errors.

[math]\displaystyle{ \% error=\frac{R_{accepted}-R_{measured}}{R_{accepted}} }[/math]

[math]\displaystyle{ \% error_{Hydrogen}\approx0.20%\,\! }[/math]

[math]\displaystyle{ \% error_{Deuterium}\approx.998%\,\! }[/math]

Conclusion

In conclusion, I am very happy with our results and our small error. Based on our small percentage error, I conclude that Ginny and I did the lab correctly and that we were able to see all the spectral lines for Hydrogen and Deuterium. I am still not sure as to why we had the most error with our data for the red spectral lines. It might be the case that we did not calibrate the spectrometer properly.