Title: Tropaeolin OO
CAS Registry Number: 554-73-4
CAS Name: 4-[[4-(Phenylamino)phenyl]azo]benzenesulfonic acid monosodium salt
Synonyms: C.I. Acid Orange 5;
p-[(
p-anilinophenyl)azo]benzenesulfonic acid sodium salt; sodium
p-[(
p-anilinophenyl)azo]benzenesulfonate; Diphenylamine Orange; Orange GS; Orange N; Orange IV; Fast Yellow; Acid Yellow D; C.I. 13080
Molecular Formula: C18H14N3NaO3S
Molecular Weight: 375.38
Percent Composition: C 57.59%, H 3.76%, N 11.19%, Na 6.12%, O 12.79%, S 8.54%
Literature References: Prepd from diphenylamine and
p-sulfobenzenediazonium chloride, followed by reaction with NaOH: Witt,
Ber. 12, 258 (1879);
Colour Index vol. 4 (3rd ed., 1971) p 4045.
Properties: Orange-yellow scales or yellow powder. Sol in water.
Use: As indicator. pH: red 1.4 to yellow 2.6.