Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

Phenolphthalein

Phenolphthalein is white or yellowish-white minute, triclinic crystals, often twinned and is odorless.

CAS 77-09-8 C20H14O4 318.3 g/mol Danger

01 · Identification

What Phenolphthalein is

Phenolphthalein is white or yellowish-white minute, triclinic crystals, often twinned and is odorless. Its molecular formula is C20H14O4 and its molecular weight is 318.3 g/mol. It melts at 263 °C.

Under the GHS it carries the signal word Danger. It is classed as carcinogens.

CAS number77-09-8
EC number201-004-7
Index number604-076-00-1
Molecular formulaC20H14O4
Molecular weight318.3 g/mol
Chemical class Carcinogens

02 · GHS classification

Hazards and label elements

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Signal wordDanger
Hazard statements assigned to Phenolphthalein
CodeHazard statement
H350 May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H341 Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H361f Suspected of damaging fertility.

Precautionary statements: P201, P280, P308, P313

This page lists only the codes assigned to Phenolphthalein. The full reference lives on the hazard statements hub, the precautionary statements hub and the GHS pictograms hub.

03 · Physical and chemical properties

Phenolphthalein properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

Property Value Conditions Source
Melting point 262.5 °C (504.5 °F) HSDB
260 °C (500 °F) range, midpoint shown CAMEO
Density 1.299 g/cm³ at 25 °C CAMEO
1.277 g/cm³ at 32 °C HSDB
Solubility 1 g dissolves in 12 ml alcohol, in about 100 ml ether; sol in dil solutions of Alkali hydroxides and hot solutions of alkali carborates forming a red soln HSDB
In water, 400 mg/L @ room temperature HSDB
Vapor pressure 6.7e-13 mmHg at 25 °C HSDB

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

04 · Source notes

Further notes on Phenolphthalein

These are descriptions rather than measured values, so they are kept out of the table above and quoted here with the source that reported them.

Solubility

Insoluble in benzene and petroleum ether; slightly soluble in carbon disulfide; soluble in ethyl ether, chloroform, and toluene; very soluble in ethanol, acetone, and pyrene.

Source: HSDB

05 · Handling and storage

Storing and handling Phenolphthalein

Storage conditions

PRECAUTIONS FOR "CARCINOGENS": Storage site should be as close as practical to lab in which carcinogens are to be used, so that only small quantities required for ... expt need to be carried. Carcinogens should be kept in only one section of cupboard, an explosion-proof refrigerator or freezer (depending on chemicophysical properties ...) that bears appropriate label. An inventory ... should be kept, showing quantity of carcinogen & date it was acquired ... Facilities for dispensing ... should be contiguous to storage area. /Chemical Carcinogens/

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

PHENOLPHTHALEIN is incompatible with alkaloids. (NTP, 1992)

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Phenolphthalein in the storage compatibility matrix →

Safety Data Sheet

Getting an SDS for Phenolphthalein

A Safety Data Sheet is written for a product, not for a substance: the supplier of the grade you actually buy issues it, so two suppliers of Phenolphthalein issue two different sheets. That is why there is no single authoritative SDS for a substance to download — what there is, is the job of collecting the sheets for the products you hold and keeping them current as suppliers revise them.

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