“…Considering that water is colorless, for the purposes of photometric analysis of water samples it is necessary in the first phase to be completed a color reaction between followed chemical species and a specific reactant, resulted color intensity being proportional to the concentration of chemical species pursued. In the second phase, the resulted colored solution is photometrically analyzed at a wavelength corresponding to followed species with the aim of establishing the optical absorbance of the solution and absorbance value is correlated with concentration through the Beer Lambert Law (Matter, 1995, Skoog,1996, Robinson,2005. Currently, in the photometry of water are used in a large-scale pre-measured dye kits for a given volume of water so that photometric analysis (Gutt S., 2010-1;2010-2;2010-3) of water can be performed in situ using portable photometers (Gutt S., 2010).…”