Determination of Absorption Coefficient of a Solution by a Simple Experimental Setup

Accurate, Photoresistor-Based, Student-Built Photometer and Its Application to the Forensic Analysis of Dyes

“…3 Note also that some authors instead adopt the natural logarithm, ln, within eq 1, in which case eq 2 still applies, but then the e-based, rather than the decadic, attenuation coefficient results, which is a factor of ln(10) ≈ 2.3 times greater. 5 Several studies have demonstrated the pedagogical benefits of introducing students to simple, modular photometers or spectrophotometers comprising only a few components to help them understand the principles behind commercial instruments used in analytical-chemistry laboratories. These studies have used a range of technologies for both the light source and the detector.…”

“…Thus, the slope of absorbance (on the y -axis) against species molar concentration (on the x -axis) for narrowband incident light with a known path length can yield the molar attenuation coefficient at this wavelength, and knowing these for a range of incident wavelengths can then identify an unknown compound by comparison of them with reference absorption spectra and attenuation coefficients . Note also that some authors instead adopt the natural logarithm, ln, within eq , in which case eq still applies, but then the e-based, rather than the decadic, attenuation coefficient results, which is a factor of ln(10) ≈ 2.3 times greater …”