ABSTRACT
This chapter examines the absorption spectrophotometer, a device for the quantitative study of electronic transitions. The first consideration is the actual energy absorbed. The energy may be determined, for instance, by the presence of carbon with a particular hybridization or by an oxygen atom in some specific configuration. The white light from the bulb passes through a slit to get rid of any extraneous reflected light from the bulb chamber and then enters a prism. The light emerging from the second slit has a relatively limited range of wavelengths and is called "monochromatic." A device that produces monochromatic light is a monochromator. The amount of light transmitted through the sample is generally measured by a photomultiplier tube. The light that strikes a photomultiplier generates an electrical current in the tube in proportion to the amount of light striking the tube. That current can then be measured by a current-measuring meter.
