Abstract Based on the “reduction” principle of laboratory waste green treatment, the identification test of nitrate ion (also called the brown ring test) was studied in terms of reagent dosage, diameter and type of test tube, the natures of ferrous salts and interference ions, etc. Simultaneously, the stability of brown ring species was characterized by UV-Vis spectrometry. The results showed that the amount of the reagent, the diameter of the test tube and the presence of ions, including NO-2, I- and SO2-3, all affected the formation of the brown ring to some extent. Under the optimized experiment conditions, the formation of the brown ring could be notably observed and the adsorption bands at 302, 450 and 587 nm were detected in the UV-Vis spectra of the brown ring species. When these results were applied in the teaching, better performance was obtained.
HE Li-Jun, HUO Cai-Xia, WANG Wen-Juan, XU Shi-Hong, GOU Hao. Study on Brown Ring Experiment by Visual Method and UV-Vis Spectroscopy[J]. Chinese Journal of Chemical Education, 2022, 43(18): 82-86.
