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Molekula

Molekula

Phenolphthalein

SKU 13440009 CAS 77-09-8 C20H14O4 MW 318.32 In stock (5+ packs) — same-day dispatch Bulk quantities on request

Supplying 4,500+ customers in over 80 countries

ISO 9001:2015 & ISO 14001:2015 certified · Supplying laboratories and industry since 2000 · Listed pack sizes are a starting point — we manufacture, source and repack to the quantity you need

Phenolphthalein is a pH indicator commonly used in titrations and as a component in certain laxatives. It appears as a white to pale yellow crystalline powder and turns pink in basic solutions. CAS: 77-09-8, Molecular Formula: C20H14O4, Molecular Weight: 318.32 g/mol. Store at ambient temperature. Signal word: Danger. Molekula supplies Phenolphthalein from research to bulk quantities with full documentation and ISO 9001:2015 traceability.

Expect a response within hours Speak to a chemist: +44 (0) 3302 000333

Example image for illustration only. Other packaging and pack sizes are available.

Often bought together

Pricing & pack sizes

Pack sizes & pricing

These pack sizes aren't a limit. Molekula manufactures, sources and repacks to order — if you need 500 kg and only see 1 kg listed, . We quote from grams to multi-tonne.

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  • 100 g — $46.90 per pack
  • 1 kg — $206.60 per pack

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Specifications

Property Value
Appearance White to off-white powder
Melting Point 260 - 263°C
Loss on Drying ≤ 0.5% (110°C)
Solubility Practically insoluble in water, soluble in alcohol.
Assay ≥ 98.0%
Sulphated Ash ≤ 0.1%
Chlorides ≤ 100mg/kg
Related Substances ≤ 0.5%
Sulphates (SO4)(2-) ≤ 200mg/kg
Identification (RAMAN) Conforms to Reference

Storage & handling

Property Value
Storage Temperature Ambient
Acidity Base

Literature values

Published physical properties of the substance, not batch specifications.

Property Value
Appearance White rhombic needles
Odour Odorless
Melting Point 262.5 °C
Water Solubility 400 mg/L at room temperature
Vapour Pressure 6.7 × 10⁻¹³ mmHg at 25 °C (Estimated)
pKa pKa = 9.7 (at 25 °C)
log P (octanol/water) 2.41

Source: PubChem CID 4764 (HSDB, DrugBank)

Identification

Property Value
SKU 13440009
CAS Number 77-09-8
IUPAC Name 3,3-bis(4-hydroxyphenyl)-2-benzofuran-1-one
EC Number 201-004-7
Molecular Formula C20H14O4
Molecular Weight 318.32
Exact Mass 318.0892
SMILES C1=CC=C2C(=C1)C(=O)OC2(C3=CC=C(C=C3)O)C4=CC=C(C=C4)O
InChIKey KJFMBFZCATUALV-UHFFFAOYSA-N
InChI InChI=1S/C20H14O4/c21-15-9-5-13(6-10-15)20(14-7-11-16(22)12-8-14)18-4-2-1-3-17(18)19(23)24-20/h1-12,21-22H
PubChem CID 4764
REACH Code Y110
TSCA Listed Yes
HTS Code 2932.20.4500
Tariff Code 2932201000

Safety & GHS

Danger
  • GHS pictogram — Health Hazard Health Hazard GHS07
  • GHS pictogram — Serious Health Hazard Serious Health Hazard GHS08

Hazard statements

  • H315 Causes skin irritation
  • H341 Suspected of causing genetic defects
  • H350 May cause cancer
  • H361f Suspected of damaging fertility.
  • H401 Toxic to aquatic life

Precautionary statements

  • P201 Obtain special instructions before use
  • P263 Avoid contact during pregnancy/while nursing
  • P273 Avoid release to the environment
  • P280 Wear protective gloves/protective clothing/eye protection/face protection
  • P302+352 IF ON SKIN: Wash with soap and water
  • P362 Take off contaminated clothing and wash before reuse

Documents

Certificate of Analysis (CoA) by batch

Enter a lot or batch number to retrieve the CoA for that specific batch. We can generate one from spec data if no PDF is on file.

Synonyms

  • Espotabs
  • Euchessina
  • Koprol
  • Laxogen
  • Phenolax
  • Phthalimetten
  • Phthalin
  • Purga
  • Purgophen
  • Trilax

Frequently asked questions

What is phenolphthalein used for?

Phenolphthalein is primarily used as a pH indicator in titrations, turning pink in basic solutions and colorless in acidic ones.

What is the chemical formula and molecular weight of phenolphthalein?

The chemical formula is C20H14O4, and the molecular weight is 318.32 g/mol.

How should phenolphthalein be stored?

Phenolphthalein should be stored at ambient temperature, away from moisture and direct light.

What grade of phenolphthalein does Molekula supply?

Molekula supplies phenolphthalein in analytical grade.

Can Molekula supply phenolphthalein in bulk?

Yes, Molekula can supply phenolphthalein in bulk quantities—please contact our sales team for details.

What documentation comes with a phenolphthalein order?

Each order includes a Certificate of Analysis (CoA) and Safety Data Sheet (SDS) with the shipment.

Ready to order or need a custom pack?

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