Hydroxy Naphthol Blue is a synthetic azo dye and metal indicator with the chemical formula C₂₀H₁₄N₂O₁₁S₃·3Na. It is also known as 3-hydroxy-4-(2-hydroxy-4-sulfo-1-naphthylazo)-2,7-naphthalenedisulfonic acid and generally occurs as dark-blue crystals. Its azo structure gives the dye characteristic color properties, while its sulfonate groups contribute to its water solubility. Hydroxy Naphthol Blue can form colored complexes with metal ions and exhibits an absorbance maximum near 650 nm when complexed with metals supporting its use in metal-ion analysis and complexometric titrations.
CAS No.: 63451-35-4
Synonyms: Hydroxy naphthol blue disodium salt, hydroxynaphthol blue indicator.
| Physical Properties | |
| Chemical formula | C20H14N2O11S3.3Na |
| IUPAC Name | trisodium;3-hydroxy-4-[(2-hydroxy-4-sulfonatonaphthalen-1-yl) diazenyl]naphthalene-2,7-disulfonate |
| Molecular weight | 620.5 g/mol |
| Solubility | Soluble in water |
| Ph | 2-3 (20 °C, 10 g/L in H2O) |
| Appearance | Black colored powder |
| Storage | Store at room temperature |
| Chemical Properties | |
| Color | Purple |
| Physical State | Solid |
| Melting Point | 801 °C |
| Boiling Point | 1413 °C |
| Odor | Odorless |
| 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 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 |
Hydroxy Naphthol Blue is a synthetic azo dye and metal indicator with the chemical formula C₂₀H₁₄N₂O₁₁S₃·3Na. It is also known as 3-hydroxy-4-(2-hydroxy-4-sulfo-1-naphthylazo)-2,7-naphthalenedisulfonic acid and generally occurs as dark-blue crystals. Its azo structure gives the dye characteristic color properties, while its sulfonate groups contribute to its water solubility. Hydroxy Naphthol Blue can form colored complexes with metal ions and exhibits an absorbance maximum near 650 nm when complexed with metals supporting its use in metal-ion analysis and complexometric titrations.
CAS No.: 63451-35-4
Synonyms: Hydroxy naphthol blue disodium salt, hydroxynaphthol blue indicator.
| Physical Properties | |
| Chemical formula | C20H14N2O11S3.3Na |
| IUPAC Name | trisodium;3-hydroxy-4-[(2-hydroxy-4-sulfonatonaphthalen-1-yl) diazenyl]naphthalene-2,7-disulfonate |
| Molecular weight | 620.5 g/mol |
| Solubility | Soluble in water |
| Ph | 2-3 (20 °C, 10 g/L in H2O) |
| Appearance | Black colored powder |
| Storage | Store at room temperature |
| Chemical Properties | |
| Color | Purple |
| Physical State | Solid |
| Melting Point | 801 °C |
| Boiling Point | 1413 °C |
| Odor | Odorless |
| 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 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 |
Hydroxy Naphthol Blue is a chemical azo dye that acts as a metal and pH indicator. It is mainly used in complexometric titrations and colorimetric analysis. Hydroxy Naphthol Blue can also be used for the analysis of calcium, alkaline earth metals, rare-earth elements, and uranium ions.
Hydroxy Naphthol Blue is also known as 3-hydroxy-4-(2-hydroxy-4-sulfo-1-naphthylazo)-2,7-naphthalenedisulfonic acid. Its chemical formula is C₂₀H₁₄N₂O₁₁S₃·3Na.
