Product Overview

Bromocresol Green Indicator dye content 95% AR/ACS (CAS No. 76-60-8) is the free-acid or sultone form of a tetrabrominated sulfonephthalein indicator. Ionisation alters the conjugated structure of the dye, producing a transition from yellow in the more acidic state to blue in the less acidic state across approximately pH 3.8–5.4. The stated dye content represents the active indicator fraction and does not independently define the complete impurity profile.

The AR/ACS grade is intended for precise preparation of indicator reagents, visual endpoint procedures and conventional analytical chemistry requiring bromocresol green with controlled transition behaviour. Its technical centre of gravity is the reproducibility of colour response and suitability for analytical solution preparation, without implying certified pH-standard or reference-material status.

Typical Applications

• Preparation of bromocresol green solutions for visual pH indication.
• Endpoint detection in acid–base titrations within the established transition region.
• Preparation of bromocresol green–methyl red mixed indicator systems for specified alkalinity procedures.
• Monitoring of weakly acidic buffers, reaction mixtures and process-development solutions.
• Spectrophotometric investigation of indicator dissociation, acidity constants and colour response.

Common Synonyms

• Bromocresol Green
• BCG
• Tetrabromo-m-cresolsulfonphthalein
• Tetrabromo-m-cresolsulphonephthalein
• Tetrabromo-m-cresolphthalein Sulfone

Storage Conditions

Store in a tightly closed container under dry conditions, protected from direct light, moisture and contamination. Close the container promptly after sampling to preserve dye content, reagent cleanliness and visual transition performance.