Chlorophenol Red (CAS: 4430-20-0) is a yellowish-brown, reddish-brown, or greenish-brown crystalline powder. It is soluble in dilute alkali hydroxides, carbonate solutions, and ammonia water, producing a red color; upon acidification, the solution turns yellow with precipitation. It is soluble in ethanol, sparingly soluble in water, and insoluble in ether and benzene.
Bromocresol Green (CAS: 76-60-8) is a triphenylmethane pH indicator with the molecular formula C₂₁H₁₄Br₄O₅S. It is readily soluble in ethanol and dilute alkaline solutions, sparingly soluble in water, and insoluble in ether and benzene. Its color transition range is pH 3.8 (yellow-green) to pH 5.4 (blue).
This product is a mixed indicator of Chlorophenol Red and Bromocresol Green. Compared with single indicators, it exhibits a more sensitive color response and is suitable for endpoint determination in weak acid-weak base titration systems. The color transitions near the endpoint are as follows: pH 5.4 (blue-purple), pH 5.8 (blue), pH 6.0 (blue with a slight purple tint), and pH 6.2 (blue-purple). The transition point of this mixed indicator is approximately pH 6.1, with yellow-green in acidic form and blue-purple in alkaline form. This product is supplied as a ready-to-use solution. Store at room temperature, protected from light, in a sealed container. Shelf life: 12 months. For research use only. Not for clinical diagnosis or other applications.
危险品化学品经营许可证（带存储）