Chrysoine resorcinol

Chrysoine resorcinol

IUPAC name Sodium 4-[(2,4-dihydroxyphenyl)diazenyl]benzenesulfonate
Other names Sodium p-(2,4-dihydroxyphenylazo)benzenesulfonate; Chrysoine; Resorcinol Yellow; Gold Yellow; Yellow T; Tropaeolin O; Tropaeolin R; C.I. Food Yellow 8; C.I. Acid Orange 6; C.I. 14270
Identifiers
CAS number	547-57-9^Y
PubChem	6093186
ChemSpider	21106427^Y
EC number	208-924-8
Jmol-3D images	Image 1 Image 2
SMILES [Na+].Oc2cc(O)ccc2/N=N/c1ccc(cc1)S([O-])(=O)=O [Na+].Oc2cc(O)ccc2/N=N/c1ccc(cc1)S([O-])(=O)=O.Oc1cccc(O)c1
InChI InChI=1S/C12H10N2O5S.C6H6O2.Na/c15-9-3-6-11(12(16)7-9)14-13-8-1-4-10(5-2-8)20(17,18)19;7-5-2-1-3-6(8)4-5;/h1-7,15-16H,(H,17,18,19);1-4,7-8H;/q;;+1/p-1/b14-13+;;^Y Key: DJYSHZPRWDNEOL-QDBORUFSSA-M^Y InChI=1/C12H10N2O5S.Na/c15-9-3-6-11(12(16)7-9)14-13-8-1-4-10(5-2-8)20(17,18)19;/h1-7,15-16H,(H,17,18,19);/q;+1/p-1/b14-13+; Key: COEZWFYORILMOM-WTMITFMSBV InChI=1/C12H10N2O5S.C6H6O2.Na/c15-9-3-6-11(12(16)7-9)14-13-8-1-4-10(5-2-8)20(17,18)19;7-5-2-1-3-6(8)4-5;/h1-7,15-16H,(H,17,18,19);1-4,7-8H;/q;;+1/p-1/b14-13+;; Key: DJYSHZPRWDNEOL-MNMGBGISBV
Properties
Molecular formula	C₁₂H₉N₂NaO₅S
Molar mass	316.27 g mol⁻¹
Appearance	Orange-yellow solid
Solubility in water	Partially soluble
Hazards
NFPA 704	1 2 0
Y (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Chrysoine resorcinol is a synthetic azo dye which was formerly used as a food additive. In Europe, it was banned as a food additive in 1977.^[1] In the US, it was banned in 1988.

Chrysoine resorcinol can be used as a pH indicator with a color change between pH 11 and pH 12.7.

Chrysoine resorcinol (pH indicator)
below pH 11.0		above pH 12.7
11.0	↔	12.7

In colorimetry it has an absorption maximum of 387 nm.

Notes

^ http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:31976L0399:EN:HTML

Chrysoine resorcinol

Notes

External links