ABSTRACT
The effectiveness of Bunsen and Kirchhoff's spectroscopy in chemical analysis was first used as a qualitative method. The quantitative basis of the spectrophotometry is that the amount of radiation absorbed at an appropriate wavelength is proportional to the concentration of the light-absorbing chemical in the sample. UV/Vis spectrophotometry is used mostly for quantitative analysis, IR spectrophotometry is mostly a qualitative technique, although quantitative applications can also be important. The tungsten filament lamp is the only common source for the visible region; it covers part of the UV region, but generally is not used below 320 to 330 nm. Calibration plots are made by linear regression or may be graphically displayed. When samples go through any pretreatment prior to the actual analysis, it should be verified and the effects from the sample preparation should be monitored. The recommended daily maintenance of the UV/Vis spectrophotometers is to keep the sample compartment and cuvettes sparkling clean.
