1.03024

Chlorophenol red

pH indicator

• Synonym(s): Chlorophenol red, 3,3′′-Dichlorophenolsulfonphthalein
• Empirical Formula (Hill Notation): C₁₉H₁₂Cl₂O₅S
• CAS Number: 4430-20-0
• Molecular Weight: 423.27
• MDL number: MFCD00005877
• UNSPSC Code: 12352106
• EC Index Number: 224-619-2

Properties

• product name: Chlorophenol red, indicator
• Quality Level: 200
• form: solid
• loss: ≤15% loss on drying, 110°C
• visual transition interval: 4.8-6.4, brownish-yellow to red-violet
• mp: 261 °C
• bulk density: 720 kg/m³
• Amax: 432-436 nm (buffer pH 4.8); 574-576 nm (buffer pH 6.4)
• storage temp.: 2-30°C
• InChI: 1S/C19H12Cl2O5S/c20-14-9-11(5-7-16(14)22)19(12-6-8-17(23)15(21)10-12)13-3-1-2-4-18(13)27(24,25)26-19/h1-10,22-23H
• InChI key: WWAABJGNHFGXSJ-UHFFFAOYSA-N

Description

Analysis Note

Identity (UV/VIS-Spectrum): passes test
Transition range: pH 4.8 - pH 6.4 brownish-yellow - red-violet
Absorption maximum λ 1 (buffer pH 4.8): 432 - 436 nm
Absorption maximum λ 2 (buffer pH 6.4): 574 - 576 nm
Spec. Absorptivity A 1%/1cm (λ1_max; 0.01g/l; buffer pH 4.8; calculated on dried substance): 450 - 600
Spec. Absorptivity A 1%/1cm (λ2_max; 0.01g/l; buffer pH 6.4; calculated on dried substance): 1000 - 1300
Loss on drying (110 °C): ≤ 15 %

Safety Information

• pictograms: GHS07
• signalword: Warning
• hcodes: H315 - H319 - H335
• pcodes: P261 - P264 - P271 - P280 - P302 + P352 - P305 + P351 + P338
• Hazard Classifications: Eye Irrit. 2 - Skin Irrit. 2 - STOT SE 3
• target_organs: Respiratory system
• Storage Class: 11 - Combustible Solids
• wgk_germany: WGK 3
• flash_point_f: Not applicable
• flash_point_c: Not applicable