Abstract Sulfur dioxide can fade fuchsin solution, and it is a typical experiment in senior high school chemistry textbooks. This study illustrated the mechanism of sulfur dioxide making fuchsin fade from experiment. On the other hand, we also discussed the mechanism based on the view of energy by using Gaussian 09 and GaussView 5.09 as well as auxiliary quantization software Multiwfn 3.3.9 to compute basic fuchsin,SO2,HSO3-,SO32- space structure, charge distribution, frontier orbital symmetry, frontier orbital energy, and the atomic contribution of frontier orbitals, and found that the fading ability of sulfur dioxide, bisulfite and sulfite to alkaline fuchsin was SO2 < HSO3- < SO32-. The chemical reaction equations for sulfur dioxide fading basic fuchsin were presented.
ZHENG Tian-Long, ZUO Xiang-Hua. Experimental and Theoretical Study on Sulfur Dioxide Making Fuchsin Fade[J]. Chinese Journal of Chemical Education, 2017, 38(9): 66-73.