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Unformatted text preview: The emission spectra of some elements INTRODUCTION: the purpose of this lab is to observe the spectra of different emission sources using a grating spectrometer and use spectrometer to identify the unknown, There will be a set of unknowns for each lab section. We will also calculate the energy levels for the electronic transmission resulting in some of the spectral lines in the emission spectrum of hydrogen. This lab relates to many things we learned in class, such as when an atom goes from a higher energy state to a lower energy state, it can emit electromagnetic radiation of certain characteristic wavelengths. This radiation is the emission spectrum of the element. Johann Balmar developed an empirical equation to fit the visible emission lines of hydrogen: λ-1 = R y (hc)-1 (n i-2 – n f-2 ) some other equations that we will use in this lab are:- Δ E = -(E f – E i ) = h υ = hc λ-1 sinQ = n λ d-1 E n = -Z 2 n-2 (h 2 (8 Π 2 m e a o 2 )-1 ) R y = 2.178 x 10-18 J PROCEDURE: 1. Observe the spectrum of some convenient sources of light 2. Verify that the sources shines brightly on the slit of the spectrometer 3. Look into the eye piece 4. Record the positions of these colored spectroscopic lines on the scale and repeat for unknowns. Data: The accepted values compared to my experimental values were not very different. Station # Element Color & λ (nm) Intensity Breadth 1...
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- Spring '08
- Noble gas, Chemical elements, argon, Neon