Emission Spectroscopy in the Undergraduate Laboratory

Abstract

Simple lab experiments using an inexpensive, solid-state computerized spectrometer can help to introduce students to analytical emission spectroscopy. A series of experiments that employ an Ocean Optics spectrometer, a Windows PC, and a fiber optic pickup are described. Line spectra of mercury and hydrogen can be used for wavelength calibration and, in the case of hydrogen, used to determine the Rydberg constant and the spacing between the energy levels in hydrogen. Continuum sources include tungsten lamps and sunlight. Students can also examine mixed spectra; for example, the spectrum of a fluorescent light shows both line and continuum behavior as does the spectrum of a deuterium lamp. Molecular band emission is studied by obtaining the spectra of fireworks—our students used sparklers. The spectra of red, green, blue, and gold sparklers show both atomic lines and molecular bands. The wavelengths of the atomic lines, in conjunction with some basic reference tables, can be used to identify the composition of the sparkler; molecular bands are more difficult to assign, but are responsible for many of the colors observed. Bands arising from salts of barium, strontium, and copper are responsible for the green, red, and blue colors seen in commercially available sparklers.

Computer Simulations of Quantum Theory of Hydrogen Atom for Natural Science Education Students in a Virtual Lab

“…It is worthwhile to mention here that it is also possible to perform Bohr's quantum model simulations for H-atom with the exact same accuracy and precision with a lower of version of Microsoft Visual Studio . NET 2008NET , 2005, and Microsoft Excel software systems [36,37].…”

Incorporating Basic Optical Microscopy in the Instrumental Analysis Laboratory

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Exploring Emission and Absorption Spectroscopy in the First-Year General Chemistry Laboratory

“…Technological advances have made devices like emission and absorption spectrometers more portable and affordable, providing opportunities to incorporate these techniques into large classes which would not have been previously feasible. While portable and comparatively inexpensive absorption spectrometers have been broadly available for several years, atomic emission can now be studied using simple emission spectrometers, studying atomic line spectra and continuous spectra from several lamp sources − and from a series of flame tests. ,− Absorption studies can be carried out using simple spectrometers, allowing for the comparison between absorption and emission instrumental techniques.…”