Reaction of FeCl2 with 1, 10-phenanthroline gives a red-colored complex that has a maximum absorbance at 510 nm. What is the best way of determining the Fe2+ concentration of a water sample without any dilution of the sample? O Use an Atomic Absorption Spectrometer O Use a Fluorescence Spectrometer O Use an Atomic Emission Spectrometer O Use a UV-vis spectrophotometer that has a Variable Path Length Slope System Question 3 1 pts In a fluorescence spectrometry, the relationship between fluorescence intensity (F) and the concentration of an analyte (c) is: F = lo(1-e-abc), where the absorptivity of the analyte (a), light pathlength (b), the intensity of the incident radiation (lo) and the quantum efficiency (D) are constant for a specific analyte and a sample holder. What is required for quantitative determination of the analyte concentration with a fluorescence spectrometer? O A laser with low intensity must be used so that the chemical structure of the analyte will not be destructed O The concentration of the analyst in the sample and the standard must be very low O Standards with a wide range of analyte concentrations must be used so that a full curve of F vs. c can be plotted. O The light source must have a wide range of wavelengths