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Supelco

Congo red (C.I. 22120)

pH indicator, Reag. Ph Eur

Synonym(s):

Congo red (C.I. 22120)

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About This Item

Empirical Formula (Hill Notation):
C32H22N6Na2O6S2
CAS Number:
Molecular Weight:
696.66
MDL number:
UNSPSC Code:
12352107
EC Index Number:
209-358-4
NACRES:
NA.21

product name

Congo red (C.I. 22120), indicator Reag. Ph Eur

Agency

reag. Ph. Eur.

Quality Level

vapor pressure

<1 Pa

form

powder

potency

143 mg/kg LD50, oral (Rat)

loss

≤5% loss on drying, 110°C

color

almost clear to slightly turbid red, 1.0g/L;water
red-brown

pH

6.7 (20 °C, 10 g/L in H2O)

mp

>360 °C

bulk density

600‑700 kg/m3

storage temp.

2-30°C

InChI

1S/C32H24N6O6S2.2Na/c33-31-25-7-3-1-5-23(25)29(45(39,40)41)17-27(31)37-35-21-13-9-19(10-14-21)20-11-15-22(16-12-20)36-38-28-18-30(46(42,43)44)24-6-2-4-8-26(24)32(28)34;;/h1-18H,33-34H2,(H,39,40,41)(H,42,43,44);;/q;2*+1/p-2

InChI key

IQFVPQOLBLOTPF-UHFFFAOYSA-L

Analysis Note

Appearance: Red-brown to brownishred powder, eventually with granular parts.
Appearance of solution (1.0 gr/l; water): Almost clear to slightly turbid, red
Transition range: pH 3.0 - pH 5.2violet - orange-red
Loss on drying (110 °C): ≤ 5 %
Sensitivity test: passes test

Pictograms

Health hazard

Signal Word

Danger

Hazard Statements

Hazard Classifications

Carc. 1B - Repr. 2

Storage Class Code

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

WGK

WGK 3


Regulatory Listings

Regulatory Listings are mainly provided for chemical products. Only limited information can be provided here for non-chemical products. No entry means none of the components are listed. It is the user’s obligation to ensure the safe and legal use of the product.

EU REACH SVHC Candidate List

CAS No.

EU REACH Annex XVII (Restriction List)

CAS No.

Certificates of Analysis (COA)

Search for Certificates of Analysis (COA) by entering the products Lot/Batch Number. Lot and Batch Numbers can be found on a product’s label following the words ‘Lot’ or ‘Batch’.

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