Chromate(5-), [4-(hydroxy-κO)-6-[2-(2-hydroxy-5-methylphenyl)diazenyl]-3-[2-[2-(hydroxy-κO)-3-nitro-5-sulfophenyl]diazenyl-κN1]-2-naphthalenesulfonato(4-)][4-(hydroxy-κO)-6-[2-(2-hydroxy-5-methylphenyl)diazenyl]-3-[2-[2-(hydroxy-κO)-5-nitro-3-sulfophenyl]diazenyl-κN1]-2-naphthalenesulfonato(4-)]-, potassium sodium