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1.01965

Supelco

Potassium hydrogen phthalate

certified secondary standard reference material for pH measurement; directly traceable to primary SRM from NIST/PTB pH(S) = 4.00₅ (25°C) Certipur®

Synonym(s):

Potassium hydrogen phthalate, KHP, Monopotassium phthalate, Phthalic acid monopotassium salt, Potassium biphthalate, Potassium phthalate monobasic

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About This Item

Empirical Formula (Hill Notation):
C8H5KO4
CAS Number:
877-24-7
Molecular Weight:
204.22
MDL number:
MFCD00013070
UNSPSC Code:
41116107
EC Index Number:
212-889-4
NACRES:
NA.24
Pricing and availability is not currently available.

grade

certified reference material

Quality Level

300

Agency

complies with DIN 19266

product line

Certipur®

potency

>3200 mg/kg LD50, oral (Rat)

pH

4.0 (20 °C, 50 g/L in H2O)

mp

295-300 °C

solubility

80 g/L

density

1.636 g/cm3

bulk density

900 kg/m3

application(s)

environmental
food and beverages
general analytical
industrial qc
pharmaceutical

format

neat

storage temp.

15-25°C

SMILES string

[K+].[O-]C(=O)c1c(cccc1)C(=O)[O-].[H+]

InChI

1S/C8H6O4.K/c9-7(10)5-3-1-2-4-6(5)8(11)12;/h1-4H,(H,9,10)(H,11,12);/q;+1/p-1

InChI key

IWZKICVEHNUQTL-UHFFFAOYSA-M

General description

Certipur® certified secondary standard reference buffers are used to precisely calibrate and monitor pH measurement instruments and buffer solutions. They are quality controlled and qualified in our ISO/IEC 17025 and ISO 17034 accredited calibration laboratories against certified primary standard reference materials (SRM) in compliance with DIN 19266, IUPAC, NIST, Ph. Eur and USP. Certipur® reference materials offer maximum accuracy, reliability and convenience and help avoid costly repeat analyses.
Please visit ISO certificates and Site Quality Self-Assessments to access the current certificates of accreditation.
Download your certificate at http://www.sigma-aldrich.com to view certified values, including uncertainty and expiry date.

Application

Potassium hydrogen phthalate [KHP; pH(S) = 4.005 (25 °C)] is a certified secondary standard reference material used as a calibration buffer standard for pH instruments or pH electrodes.

Features and Benefits

  • The product is delivered with a comprehensive, batch-specific Certificate of Analysis showing the relevant data for the quality management system.
  • The pH value of this Certipur® buffer solution is qualified using differential potentiometry with two platinum hydrogen electrodes against NIST & PTB primary reference materials [pH(S) = 4.005 (25 °C)].
  • This buffer standard has a guaranteed shelf life of 4 years.
  • Potassium hydrogen phthalate buffer is a Certified Reference Material (CRM) offered in neat format. Solution of this standard can be prepared in-house per instructions in European Pharmacopoeia (Ph. Eur. 2.2.3).
  • Intended for extremely precise calibration, qualification and monitoring of pH instruments and routine assessment of their performance.

Legal Information

CERTIPUR is a registered trademark of Merck KGaA, Darmstadt, Germany

Storage Class Code

13 - Non Combustible Solids

WGK

WGK 1

Flash Point(F)

387.1 °F - Pensky-Martens closed cup

Flash Point(C)

197.3 °C - Pensky-Martens closed cup

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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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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