Formula C30H20N4O11S3 | ||
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Fast Sulphon Black F is a complexometric indicator used with EDTA, almost exclusively used in copper complexation determination.
Application
Fast Sulphon Black is purple when complexed with copper, and turns green when titrated against EDTA, as the EDTA displaces it, being the better complexing agent due to the chelate effect.
References
Fast Sulphon Black F Wikipedia(Text) CC BY-SA