Lab - Atomic Spectroscopy
Uploaded by erobinson on Apr 30, 2004
Atomic Spectroscopy
Introduction:
The purpose of this lab is to learn about light and the light emitting properties of different atoms. We will use a spectrometer to observe these relationships.
Data:
[img:c4daeb4fff]http://www.collegepimp.com/echeat/lab8.gif[/img:c4daeb4fff]
Discussion:
The purpose of this lab was to learn about spectroscopy, which would give us a better understanding about the light properties of atoms. By observing light emission and absorption we learn more about the changes in energy states of atoms. We used a spectrometer and the naked eye to observe visible changes of these energy states.
The first part of the lab was to calibrate our spectroscopes. This was not done in the sense I had imagined it, which would be to actually actively calibrate the spectroscope so the reading would be correct. Instead, we had to find the level of error in our spectroscopes, then correct for it each time we took a reading. After observing the emission of mercury we created a graph with a trend line to help us determine the actual wavelength of light.
In part 2 we observed the emission of hydrogen. We found that hydrogen emits violet, blue, green, and red light in the visible spectrum. We calculated a maximum of a 2.88% error, which tells us two things: one, that our spectrometer has been calculated fairly accurately, and that we are observing the correct colors because they correlate so closely to the accurate . We also found the change in energy states through trial and error for hydrogen. As expected, the higher the initial energy state, the shorter the wavelength, since there is a greater change in energy than between that of a lower energy state. 410nm had an initial energy state of 6. Energy states went consecutively down as the wavelength increased, until the initial energy state was 3 at 565nm.
In part 3, we observed the light emission from various Alkali and Alkaline Earth Metals. The purpose of this was to give us an even further understanding of the relationship between atomic structure and the energy emitted and its relationship with wavelength. Based on the visible light spectrum, LiCl emitted the least energy based on the bright red color, and KCl would have emitted the most energy based on the white-violet color.
A source of possible error is in the calibration of the spectrometer. If the correction for the spectrometer is off, all further calculations will be adversely affected. Another source of error would be if the wire...