General description
The certified secondary standard reference buffer solution of potassium dihydrogen phosphate/disodium hydrogen phosphate is gravimetrically prepared using high-quality reagents in high-purity water. Its pH value is analyzed by differential potentiometry with two platinum hydrogen electrodes against primary certified reference materials from NIST & PTB. Also, the pH analysis uses the 5-point calibration method, following DIN 19268, against certified primary reference standards as per DIN 19266.
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
The buffer solution can be used for the calibration, qualification, and monitoring of pH measuring instruments and as a control for testing other buffer solutions.
Features and Benefits
Available in solution format in a secure 100 mL high-density plastic bottle
Subjected to detailed stability studies as per ISO Guide 35
Product label having relevant information on order number, article description, lot number, expiry date and safety data, in accordance with ISO Guide 31
Accompanied with a detailed and batch-specific certificate of analysis (CoA) for an effective quality management system
Measured and qualified in ISO/IEC 17025 and ISO 17034 accredited laboratory
Traceable to SRMs from NIST and primary certified reference standards from PTB
Analysis Note
pH-value: 7.414 – 7.420
For complete data see the enclosed certificate
Legal Information
CERTIPUR is a registered trademark of Merck KGaA, Darmstadt, Germany

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