Physics307L:People/Frye/NeonExcitation

Excitation Levels of Neon
The purpose of this lab was to find the excitation energy levels of neon gas. We followed the procedure outlined in Gold's lab manual for lab number 6. We set up the equipment according to the manual. We took measurements of the current while varying the accelerating voltage in order to find peaks and valleys in the graph of current vs voltage. From this we are able to find the excitation levels of whatever gas is in the tube, in this case neon. We first did a 'rough' scan from 0V to 30V at one volt intervals to get a general idea what the current was doing. We then graphed that data and decided to scan more finely in the voltage range 15V to 22V, we did the second scan at 0.1V intervals. We also did a second scan of the same accelerating voltage range but changed the filament voltage from 1.8V to 2.1V. Both of these sets of data produced peaks that were close to the accepted values for the excitation energy of neon as well as the ionization energy. What i did was average the voltage where the first peak was on the first trial with that of the second trial. The same for the second peak and the ionization energy. I then compared these measured values to the accepted values and obtained the following results:


 * We found the first peak to be at 16.1eV +/- 0.1eV with relative error compared to the accepted value of 3.6%


 * The second peak at 18.2eV +/- 0.1eV with relative error compared to the accepted value of 2.4%


 * The ionization energy of neon at 21.18eV +/- 0.1eV with relative error compared to the accepted value of 1.8%


 * the +/- 0.1eV uncertainty here comes from our uncertainty in measuring the voltages since we only measured in 0.1V intervals.

Pictures


[[Media:09262010Excitaion of Neon.xls|Download spreadsheet of our data]]

Links
My Lab Notebook