Orange IV is a synthetic azo dye known for its bright orange color and is chemically identified as the sodium salt of 4-(4-nitrophenylazo)resorcinol. It is also known as Tropaeolin OO and Acid Orange 5, with the chemical formula C₁₈H₁₄N₃NaO₃S. The dye is readily soluble in water and produces a strong orange-colored solution. Orange IV shows a distinct color response to changes in pH appearing red under strongly acidic conditions and orange-yellow at higher pH. It is primarily used as a biological staining dye and pH indicator in laboratory research.
CAS No.: 554-73-4
Synonyms: Acid Orange 5, Aniline Yellow, Diphenylamine Orange, Tropaeolin OO.
| Physical Properties | |
| Chemical formula | C18H14N3NaO3S |
| IUPAC Name | sodium 4-{2-[4-(phenylamino)phenyl] diazen-1-yl}benzene-1-sulfonate |
| Molecular weight | 377.39 g/mol |
| Appearance | Orange-yellow scales or yellow powder |
| Solubility | Soluble in water and ethanol |
| Storage | Store at room temperature |
| Chemical Properties | |
| Color | Light Brown |
| Physical State | Solid |
| λmax | 446.0 to 450.0 nm |
| Melting Point | >300°C |
| Pictograms : |  |
| Hazard Statements : | H315 Causes skin irritation H319 Causes serious eye irritation H335 May cause respiratory irritation |
| Precautionary Statements: | P280: Wear protective gloves/eye protection P302+P352: IF ON SKIN: Wash with plenty of soap and water P305+P351+P338: IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing |
Orange IV is a synthetic azo dye known for its bright orange color and is chemically identified as the sodium salt of 4-(4-nitrophenylazo)resorcinol. It is also known as Tropaeolin OO and Acid Orange 5, with the chemical formula C₁₈H₁₄N₃NaO₃S. The dye is readily soluble in water and produces a strong orange-colored solution. Orange IV shows a distinct color response to changes in pH appearing red under strongly acidic conditions and orange-yellow at higher pH. It is primarily used as a biological staining dye and pH indicator in laboratory research.
CAS No.: 554-73-4
Synonyms: Acid Orange 5, Aniline Yellow, Diphenylamine Orange, Tropaeolin OO.
| Physical Properties | |
| Chemical formula | C18H14N3NaO3S |
| IUPAC Name | sodium 4-{2-[4-(phenylamino)phenyl] diazen-1-yl}benzene-1-sulfonate |
| Molecular weight | 377.39 g/mol |
| Appearance | Orange-yellow scales or yellow powder |
| Solubility | Soluble in water and ethanol |
| Storage | Store at room temperature |
| Chemical Properties | |
| Color | Light Brown |
| Physical State | Solid |
| λmax | 446.0 to 450.0 nm |
| Melting Point | >300°C |
| Pictograms : | |
| Hazard Statements : | H315 Causes skin irritation H319 Causes serious eye irritation H335 May cause respiratory irritation |
| Precautionary Statements: | P280: Wear protective gloves/eye protection P302+P352: IF ON SKIN: Wash with plenty of soap and water P305+P351+P338: IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing |
Orange IV is mainly used as a biological staining dye and pH indicator in laboratory research. It is also used in textile dyeing, coloring applications and research involving dyes and pigments.
Orange IV is also known as Tropaeolin OO and Acid Orange 5. The chemical formula of Orange IV is C₁₈H₁₄N₃NaO₃S. It generally appears yellow-orange to bright orange and produces an orange-colored aqueous solution.
