Preparation
4-Amino-3-hydroxynaphthalene-1-sulfonic acid diazo, and?8-Hydroxynaphthalene-1-sulfonamide coupling, and then make its formed chromium complex.
Properties and Applications
green light blue. Soluble in water for green light blue. The strong sulfuric acid for green, diluted to blue. Join the hydrochloric acid solution for blue solution and precipitation; Add sodium hydroxide for purple.