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1.06076

Supelco

Methyl red (C.I. 13020)

pH indicator, ACS, Reag. Ph Eur

Synonym(s):

Methyl red (C.I. 13020), 4-Dimethylaminoazobenzene-2′-carboxylic acid

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Estimated to ship onApril 17, 2025


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25 G
$58.90
100 G
$206.00

About This Item

Empirical Formula (Hill Notation):
C15H15N3O2
CAS Number:
Molecular Weight:
269.30
MDL number:
UNSPSC Code:
12352107
EC Index Number:
207-776-1
NACRES:
NA.05

$58.90


Estimated to ship onApril 17, 2025


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Product Name

Methyl red (C.I. 13020), indicator ACS,Reag. Ph Eur

grade

ACS reagent

Quality Level

agency

reag. Ph. Eur.
suitable for SM 4500 - NH3

form

powder
solid

loss

≤5% loss on drying, 110°C

color

red to red-violet

visual transition interval

4.4-6.0, red to yellow

mp

178-182 °C

bulk density

300‑500 kg/m3

Amax

427-437 nm (buffer pH 6.2)
523-526 nm (buffer pH 4.5)

storage temp.

2-30°C

SMILES string

N(C)(C)c1ccc(cc1)N=Nc2c(cccc2)C(=O)O

InChI

1S/C15H15N3O2/c1-18(2)12-9-7-11(8-10-12)16-17-14-6-4-3-5-13(14)15(19)20/h3-10H,1-2H3,(H,19,20)

InChI key

CEQFOVLGLXCDCX-UHFFFAOYSA-N

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Analysis Note

Identity (UV/VIS-Spectrum): passes test
Appearance: Red to red-violet powder, eventually with granular parts.
Clarity of solution (1 g/l; ethanol): passes test
Melting point (capillary method, temperatur measerment in the heating block): 179 - 182 °C
Transition range: pH 4.4 - pH 6.0 Red - yellow
Absorption maximum (buffer pH 4.5): 523 - 526 nm
Absorption maximum (buffer pH 6.2): 427 - 437 nm
Spec. Absorptivity A 1%/1cm (λmax; 0.005 g/l; buffer pH 4.5; calculated on anhydrous substance): 1350 - 1500
Spec. Absorptivity A 1%/1cm (λmax; 0.005 g/l; buffer pH 6.2; calculated on anhydrous substance): 700 - 800
Transition range (according to ACS): passes test
Loss on drying (110 °C): ≤ 5 %

Storage Class

11 - Combustible Solids

wgk_germany

WGK 2

flash_point_f

Not applicable

flash_point_c

Not applicable


Certificates of Analysis (COA)

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Questions

1–2 of 2 Questions  
  1. How can I determine the shelf life / expiration / retest date of this product?

    1 answer
    1. If this product has an expiration or retest date, it will be shown on the Certificate of Analysis (COA, CofA). If there is no retest or expiration date listed on the product's COA, we do not have suitable stability data to determine a shelf life. For these products, the only date on the COA will be the release date; a retest, expiration, or use-by-date will not be displayed.
      For all products, we recommend handling per defined conditions as printed in our product literature and website product descriptions. We recommend that products should be routinely inspected by customers to ensure they perform as expected.
      For products without retest or expiration dates, our standard warranty of 1 year from the date of shipment is applicable.
      For more information, please refer to the Product Dating Information document: https://www.sigmaaldrich.com/deepweb/assets/sigmaaldrich/marketing/global/documents/449/386/product-dating-information-mk.pdf

      Helpful?

  2. How is shipping temperature determined? And how is it related to the product storage temperature?

    1 answer
    1. Products may be shipped at a different temperature than the recommended long-term storage temperature. If the product quality is sensitive to short-term exposure to conditions other than the recommended long-term storage, it will be shipped on wet or dry-ice. If the product quality is NOT affected by short-term exposure to conditions other than the recommended long-term storage, it will be shipped at ambient temperature. As shipping routes are configured for minimum transit times, shipping at ambient temperature helps control shipping costs for our customers. For more information, please refer to the Storage and Transport Conditions document: https://www.sigmaaldrich.com/deepweb/assets/sigmaaldrich/marketing/global/documents/316/622/storage-transport-conditions-mk.pdf

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