Chemical SciencesMolecular Absorption Spectroscopy Lab →List Of Experiments

Familiarization with the UV-Visible Absorption Spectroscopy

Originally spectrum referred to the dispersion of visible light according to its wavelength by a prism. In modern science spectroscopy refers to the study of the interaction between matter (viz., atoms, molecules, ions, and solids) and electromagnetic radiation as a function of the radiation energy (often expressed in terms of frequency or wavelength of radiation). When light passes through a medium, some of the light energy may be absorbed, in addition to other processes such as scattering, surface reflectance, etc. If there is a fractional absorption of radiation (energy) and the rest of the radiation passes through the medium, then the medium is called a transparent medium to that particular transmitting radiation. When a portion of the radiation is absorbed from a passing continuous radiation through a transparent substance, the absorbed wavelengths remain absent from the residual emerging radiation spectrum. Thus an analysis of the transmitting radiation produces an absorption spectrum. Spectrophotometers are devices used to measure the wavelength distribution of absorbed or transmitted light. In UV-Visible absorption spectroscopy, samples absorb ultra-violet or visible radiations. UV-Visible absorption spectroscopy provides useful qualitative and quantitative information regarding solid, liquid and gaseous samples and many physical and chemical processes that occur in these samples.