Phenolphthalein CAS 77-09-8

Chemical Name: Phenolphthalein

CAS No.: 77-09-8

Molecular Fomula: C20H14O4

Chemical Structure:Phenolphthalein Structure

Molecular weight: 318.32

Appearance: A white powder, practically insoluble in water, soluble in alcohol.

Assay: 98.0%-101.0%(C2OHi4O4)


Phenolphthalein CAS 77-09-8

Item Specifications
Characteristics A white or almost white powder, practically insoluble in water, soluble in alcohol.
Melting Point It melts at about 260℃
Identification A:Positive B:Positive
Appearance of solution The solution is clear and not more intensely coloured than reference solution Y7
Related substances Less than 0.5%
Heavy metals Not more than0.001%
Acidity or alkalinity Complies
Chlorides Not more than 0.01%
Sulphates Not more than 0.02%
Loss on drying Not more than 0.5%
Sulphated ash Not more than 0.1%
Assay 98.0%-101.0%(C2OHi4O4)
Microorganism TPC<1000cfu/g
Y and M <100cfu/g
E-coli – absent
Staphylococcus Aureus-Absent
Pseudomonas Aeruginosa-Absent
Albicans Saccharomyces-Absent


Phenolphthalein Usage

1. Phenolphthalein is a weak organic acid. It is white or slightly yellowish fine crystals at room temperature. It is odorless and tasteless. It is hardly soluble in water but easily soluble in alcohol (ethanol) and ether. Dissolved in alcohol solution to make acid-base indicator, it is colorless in acid solution, red in lye or alkali metal carbonate solution, but if it is in concentrated alkali solution, it will generate colorless trimetal The salt, the red faded. In view of this characteristic, it is often used as an indicator of acid-base titration in laboratories. The color range of PH value is 8.2~10.0, from colorless to red. When the phenolphthalein reagent is dripped into water or a neutral, acidic aqueous solution, white turbidity will appear. This is because alcohol is easily soluble in water and the phenolphthalein, which is hardly soluble in water, precipitates out in the reagent.

2. Pharmaceutical raw materials for the pharmaceutical industry: suitable for habitual stubborn constipation, with various dosage forms such as tablets and suppositories.
3. For organic synthesis: mainly used for the synthesis of plastics, especially for the synthesis of phthalazinone polyaryl ether ketone polyaryl ether ketone polymers, which have excellent heat resistance, water resistance and chemical resistance Corrosion, heat aging resistance and good processing and formability, fibers, coatings and composite materials made from them have soon been widely used in electronic appliances, mechanical equipment, transportation, aerospace, atomic energy engineering and military fields.


PhenolphthaleinPackaging and Shipping

Fiber Drum,25kg


Phenolphthalein Storage

Store in a cool, dry place.


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