User:Manuel Franco Jr./Notebook/Physics Lab 307/2008/10/01

Balmer Series Lab

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The Balmer Series For Hydrogen and Deuterium Lab Partner: David Objective The objectives are: calibrate an optical spectrometer using the given mercury spectrum in the lab manual, investigate hydrogen and deuterium, compare them, and determine the Rydberg constant for hydrogen. Equipment Adam Hilger London Spectrometer. A Serial Number 12610 was found. Power Supply, 5000V 10mA,(Model: Sp200 from Electro Technic products) A Prism A Hydrogen Tube from Cenco Scientific Company. A Deuterium Tube from Cenco Scientific Company. A Mercury Tube from Cenco Scientific Company. Images for Experiment Calibration We first had to calibrate the spectrometer by using mercury (Hg) and the table spectral lines of Hg (Lab Manual: Section 4.3). Hg Spectral Lines 404.7 nm (deep violet very hard to see!!) 435.8 nm violet skip (very weak blue-green) 546.1 nm green 577.0 nm yellow 579.0 nm yellow 690.75 nm red The calibration was repeated as need. The colors were aligned using the cross hairs in the eyepiece. We moved the prism as need. Once we calibrated the spectrometer, we adjusted the slit to .7 mm. We adjusted the slit as needed, but we stayed within the bounds of .5 and 1 mm. As we were calibrating Koch mention the us that the gears in the dial has what is called "slop." So when we calibrated the spectrometer, we calibrated it going counterclockwise. That means all the data measurements have to be taken the same way. If we were to take a data point clockwise, or opposite to direction we initially used to calibrate, our data would be off by about 1 nm. So all the data was gathered going in a counterclockwise direction on the dial. Data This is what you should see[1]. Hydrogen Measurements Color Measurement 1 (nm) Measurement 2 (nm) Measurement 3 (nm) Measurement 4 (nm) Red 657.8 659.9 659.5 659 Blue/Green 486 486 486.1 485.9 Violet 433.8 434 434.2 434.4 Dim. Violet 409.7 409.8 409.3 410.1 Deuterium Measurements Color Measurement 1 (nm) Measurement 2 (nm) Measurement 3 (nm) Measurement 4 (nm) Red 659 659.9 659.5 658.1 Blue/Green 485.9 485.9 486 486 Violet 434.2 434.2 434.2 434.2 Dim. Violet 409.8 409.7 409.8 409.3 Data Analysis SJK 02:17, 22 October 2008 (EDT) 02:17, 22 October 2008 (EDT) I looked at your spreadsheets. They are great! You also have really nice graphs in there. Graphs are an essential part of presenting data...you should upload the images and include them in your report! This is the Spread Sheet 1 in where I did all my analysis for hydrogen and deuterium. Color Wavelengths for H Wavelengths for D Red 656.1 +/- .5 nm 659.13 +/- .03 nm Blue/Green 486.00 +/- .04 nm 485.95 +/- 0.03 nm Violet 434.1 +/- .1 nm 434.2 +/- 0.1 nm Dim. Violet 409.7 +/- .1 nm 409.65 +/- .12 nm As for the Rydberg constant, I found the constant in this word Spread Sheet 2. I used this equation to find the slope http://upload.wikimedia.org/math/5/a/0/5a05645dc256a0aca0ab1c9cf97b6525.png [2]. And this is the actual measurement thereof http://upload.wikimedia.org/math/7/b/6/7b625152ea50ad187556f8d158b79aff.png [3]. Lab Summary This is my lab summary. References Lab Manual: Sections 4.1-4.6 Wikipedia article on Balmer Series Wikipedia article on Rydberg Constant Links Physics307L Lab Notebook Course Page User Page