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1.08294

Supelco

Thorin

indicator for sulfate titration

Synonym(s):

Thorin, 1-(2-Arsonophenylazo)-2-hydroxy-3,6-naphthalene-disulfonic acid sodium salt, 2-(2-Hydroxy-3,6-disulfo-1-naphthylazo)-benzene-arsonic acid sodium salt

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About This Item

Empirical Formula (Hill Notation):
C16H11AsN2Na2O10S2
CAS Number:
3688-92-4
Molecular Weight:
576.30
UNSPSC Code:
12352103
EC Index Number:
222-993-1
NACRES:
NB.21

product name

Thorin, indicator for sulfate titration

Quality Level

200

form

solid

impurities

≤25% Water (Karl Fischer)

pH

6.1 (20 °C, 10 g/L in H2O)

bulk density

700 kg/m3

λmax

480-490 nm (propan-2-ol)

storage temp.

2-30°C

InChI

1S/C16H13AsN2O10S2.2Na/c20-16-14(31(27,28)29)8-9-7-10(30(24,25)26)5-6-11(9)15(16)19-18-13-4-2-1-3-12(13)17(21,22)23;;/h1-8,18H,(H2,21,22,23)(H,24,25,26)(H,27,28,29);;/q;2*+1/p-2/b19-15+;;

InChI key

ZQMPNLOZJUWHSA-WTBAQZMLSA-L

Analysis Note

Identity (UV/VIS-Spectrum): passes test
Absorption maximum λmax. (Propan-2-ol): 480 - 490 nm
Spec. Absorptivity A 1%/1cm (λmax; 0.025 g/l;propan-2-ol; calc. on anhydrous substance): 250 - 350
Water (according to Karl Fischer): ≤ 25 %
Suitability as indicator (for sulfate titration): passes test

Pictograms

Skull and crossbonesEnvironment
GHS06,GHS09

Signal Word

Danger

Hazard Statements

H301 + H331 - H410

Hazard Classifications

Acute Tox. 3 Inhalation - Acute Tox. 3 Oral - Aquatic Acute 1 - Aquatic Chronic 1

Storage Class Code

6.1A - Combustible, acute toxic Cat. 1 and 2 / very toxic hazardous materials

WGK

WGK 3

Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

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 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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