Description
Phenolphthalein, ACS reagent, 2.5KG
Synonym(s):
3,3-Bis(4-hydroxyphenyl)-1(3H)-isobenzofuranone
Empirical Formula (Hill Notation):
C20H14O4
CAS Number:
77-09-8
Molecular Weight:
318.32
Colour Index Number:
764
Beilstein/REAXYS Number:
284423
EC Number:
201-004-7
MDL number:
MFCD00005913
UNSPSC Code:
12171500
PubChem Substance ID:
24846716
NACRES:
NA.47
Properties
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.[1] 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.[2]
It is present as a nonionic, lipophilic lactone in aqueous neutral solutions. It exists as a hydrophilic dianion in 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[3]
- the determination of the depth of carbonation in concrete[4]
- 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 is colorless in acidic solutions and turns pink in basic solutions.
Principle
Phenolphthalein undergoes structural modification when there is a change in pH or in the structural state of water.[1] It is a nonionic, lipophilic colorless lactone in aqueous neutral solutions and a hydrophilic dianion in alkaline solutions.[2]
Safety Information
pictograms
GHS08,GHS07
signalword
Danger
hcodes
H315,H341,H350,H361f
pcodes
P202 - P264 - P280 - P302 + P352 - P308 + P313 - P332 + P313
Hazard Classifications
Carc. 1B - Muta. 2 - Repr. 2 - Skin Irrit. 2
wgk_germany
WGK 3
flash_point_f
Not applicable
flash_point_c
Not applicable
ppe
Eyeshields, Gloves, type P3 (EN 143) respirator cartridges