Description

Phenolphthalein is a classic synthetic organic compound widely recognized as a vital pH indicator in analytical chemistry. Its distinct color change from colorless in acidic solutions to a vibrant pink/fuchsia in basic solutions makes it an indispensable tool for visual endpoint determination in titrations and educational demonstrations. This high-purity chemical is essential for laboratories, quality control departments, and manufacturing processes across multiple industries. We supply Phenolphthalein CAS NO 5768-87-6 to the global market, ensuring consistent quality and reliable performance for your critical applications.

Application

• Acid-Base Titration Indicator: Primary use in volumetric analysis for determining the concentration of acids and bases with a transition range of pH 8.2 to 10.0.
• Laboratory Reagent & Educational Kits: A fundamental component in school, university, and industrial laboratory reagent sets for chemistry experiments.
• Manufacturing of pH Test Papers & Strips: Used as the active color-changing agent in the production of qualitative pH test papers.
• Quality Control (QC) Testing: Employed in various industrial QC protocols, including water analysis and chemical process monitoring.
• Research & Development: Serves as a model compound and starting material in organic synthesis and chemical research.
• Forensic Analysis: Historically used in presumptive tests for blood (Kastle-Meyer test), though newer methods are now preferred.

Basic Information

Product Name	Phenolphthalein
CAS No.	5768-87-6
Molecular Formula	C20H14O4
Molecular Weight	318.33 g/mol
Synonyms	3,3-Bis(4-hydroxyphenyl)-1(3H)-isobenzofuranone; 3,3-Bis(4-hydroxyphenyl)phthalide; Phenolphthalein Indicator; Dihydroxyphthalophenone; Phthalide, Phenol; NSC 4765; 1(3H)-Isobenzofuranone, 3,3-bis(4-hydroxyphenyl)-; Phenolphthalein BP/USP
EINECS	227-274-9

Quality Control

Our Phenolphthalein is manufactured under strict quality management systems. Each batch undergoes rigorous analytical testing to ensure it meets high-purity standards suitable for analytical and laboratory use. Certificates of Analysis (COA) detailing purity, identity, and specific impurity profiles are available upon request. We can supply grades compliant with various pharmacopeial standards (e.g., BP, USP) based on customer requirements.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, well-ventilated area at room temperature (15-25°C). Keep away from incompatible materials such as strong oxidizing agents and strong bases.

Specification

Item	Specification
Appearance	White to faintly yellowish-white crystalline powder
Identification (IR)	Conforms to standard
Assay (HPLC)	≥ 98.0%
Melting Point	258°C - 263°C
Loss on Drying	≤ 0.5%
Sulfated Ash	≤ 0.1%
Solubility (in Ethanol)	Clear, colorless solution
pH Transition Range	8.2 (colorless) to 10.0 (pink/fuchsia)

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.