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13: Introduction to Ultraviolet/Visible Absorption Spectrometry

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    • 13.1: Transmittance and Absorbance
      As light passes through a sample, its power decreases as some of it is absorbed. This attenuation of radiation is described quantitatively by two separate, but related terms: transmittance and absorbance.
    • 13.2: Beer's Law
      Beer's law connects absorbance to the concentration of the absorbing species. In this section we derive Beer's law and consider some of its limitations.
    • 13.3: Effect of Noise on Transmittance and Absorbance Measurements
      In absorption spectroscopy, precision is limited by indeterminate errors—primarily instrumental noise—which are introduced when we measure absorbance. Precision generally is worse for low absorbances and for high absorbances . We might expect, therefore, that precision will vary with transmittance.
    • 13.4: Instrumentation
      As covered in Chapter 7, the basic instrumentation for absorbance measurements consists of a source of radiation, a means for selecting the wavelengths to use, a means for detecting the amount of light absorbed by the sample, and a means for processing and displaying the data. In this section we consider two other essential components of an instrument for measuring the absorbance of UV/Vis radiation by molecules: the optical path that connects the source to the detector and a means for placing t

    This page titled 13: Introduction to Ultraviolet/Visible Absorption Spectrometry was last modified on Sun, 28 Aug 2022 20:54:34 GMT and is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by David Harvey.