For detection of concentration of a compound in spectrometer, a wavelength of light is used, for which sample shows maximum absorption, and hence, concentration can be find out. But for a compound whose absorption wavelength is unknown, now how to find out the wavelength for which this compound will show absorption and hence standard ?
The method is to prepare a solution of the compound in the appropriate solvent and measure its absorbance over a range of evenly spaced wavelengths in a spectrophotometer by scanning the monochromator. Care must be taken to be sure that the compound is fully dissolved and that the absorbance at the peak wavelength is within the detection range of the instrument (an absorbance of about 1 unit is satisfactory). Any background absorbance from the solvent should be subtracted by measuring the absorbance of the solvent alone at the same range of wavelengths.
Thank you sir, but sir cann't we use colorimeter to find its colour and therefore its wavelength and hence maximum absorbance.
I don't know. I'm familiar with spectrophotometers, but not colorimeters.
You can use scan mode setting and reading absorbance from 190 nm to 1200 nm wavelength in spectrophotometers.
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