Light absorbed invisible range

When he returned, the temperature had risen dramatically. He postulated an invisible band of light beyond (in Latin, infra) red, or infrared. Since his prism was glass and glass absorbs mid-range infrared (IR) radiation, the band was truly near infrared (short-wavelength IR). This work was duly reported [1] and essentially forgotten. 

The chemist in the automobile industry may be called upon not only for the manufacture of these compounds but also for the analysis in order to maintain the proper concentration of the compound. The detection in an HPLC system is most widely accomplished by UV-visible detectors. Most compounds used in production chemicals have chromophores that are detectable in the UV region. Table 2.6 shows molar absorption values for common functional groups [5], Care must be taken that the solvent used in the analysis is invisible to the analysis. As can be seen from Table 2.6, typical detection range is 180-210 nm. A chromophore is the region between two different molecular orbitals and will absorb UV light due to the conjugated system of electrons or to a metal complex bound to a transition metal to a ligand. 

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