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105945

Phenolphthalein

ACS reagent

Synonym(s):

3,3-Bis(4-hydroxyphenyl)-1(3H)-isobenzofuranone

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About This Item

Empirical Formula (Hill Notation):
C20H14O4
CAS Number:
77-09-8
Molecular Weight:
318.32
EC Number:
201-004-7
UNSPSC Code:
12171500
NACRES:
NA.47
PubChem Substance ID:
24846716
MDL number:
MFCD00005913
Colour Index Number:
764
Beilstein/REAXYS Number:
284423
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grade

ACS reagent

Quality Level

200

form

powder

technique(s)

titration: suitable

visual transition interval

8.0-10, colorless to red

mp

261-263 °C (lit.)

solubility

acetone: soluble

density

1.27 g/cm3 at 32 °C

λmax

374 nm (2nd), 552 nm

application(s)

diagnostic assay manufacturing
hematology
histology

storage temp.

room temp

SMILES string

Oc1ccc(cc1)C2(OC(=O)c3ccccc23)c4ccc(O)cc4

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

InChI key

KJFMBFZCATUALV-UHFFFAOYSA-N

General description

Phenolphthalein is an indicator for acid-base titration reactions. It changes from colorless to violet-red between pH 8.3-9.8, it is red in extremely acidic solutions, and colorless in extremely alkaline solutions.

It is present as a nonionic, lipophilic lactone in aqueous neutral solutions. It exists as a hydrophilic dianion in alkaline solutions.

Application

Phenolphthalein has been commonly used as an indicator in the fields of biology and medicine. Its applications include:

  • the development of novel technique to monitor the vacuum freeze-drying process
  • the determination of the depth of carbonation in concrete
  • the utilization of liquid marbles to sense gaseous environmental components
  • the estimation of total acidity in vinegar
  • the assessment of sodium hydroxide penetration into potatoes following chemical peeling
  • as a model organic compound in the evaluation of the capture efficiency of various cyclodextrin constructs such as nanofiber-CD

Biochem/physiol Actions

Phenolphthalein undergoes structural modification when there is a change in pH or in the structural state of water. It is a nonionic, lipophilic colorless lactone in aqueous neutral solutions and a hydrophilic dianion in alkaline solutions.
Phenolphthalein is colorless in acidic solutions and turns pink in basic solutions.

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pictograms

Health hazardExclamation mark
GHS08,GHS07

signalword

Danger

Hazard Classifications

Carc. 1B - Muta. 2 - Repr. 2 - Skin Irrit. 2

Storage Class

6.1C - Combustible acute toxic Cat.3 / toxic compounds or compounds which causing chronic effects

wgk

WGK 3

flash_point_f

Not applicable

flash_point_c

Not applicable

ppe

Eyeshields, Gloves, type P3 (EN 143) respirator cartridges

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Certificates of Analysis (COA)

Lot/Batch Number
BCCM7361
BCCL3444
BCCK1147
MKCT3743
MKCR8728

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Conn?s Biological Stains: A Handbook of Dyes, Stains and Fluorochromes for Use in Biology and Medicine (10th ed.)
RW Horobin, JW Kiernan (Eds.)
Conn?s Biological Stains (2002)
Using phenolphthalein as a promising indicator to monitor the vacuum freeze-drying process
Liu, et al.
Materials Letters, 139 (2015)
The experimental investigation of concrete carbonation depth
Cheng-Feng Chang, Jing-Wen Chen
Cement and Concrete Research, 36(9) (2006)
View All Related Papers

Global Trade Item Number

SKUGTIN
105945-500G04061835570157
105945-2.5KG04061833646014
105945-100G04061835570140