Buffer solution

General description
The certified buffer solution (citric acid/sodium hydroxide/hydrogen chloride) is gravimetrically prepared using high-quality reagents, as per DIN EN ISO/IEC 17025. Its pH value of 4.00 at 25°C is calculated using a combined glass electrode following a 5-point calibration method. The measurement is made following DIN 19268 using reference buffer solutions compliant to DIN 19266, NIST, IUPAC, Ph. Eur, and USP. Its pH value is strongly dependent on the temperature and therefore a constant temperature must be maintained during its use.

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Application
The buffer solution is used as a calibration standard in analytical procedures for pH measuring instruments or pH electrodes and as a control for measuring the pH of solutions.
Features and Benefits
Measured and qualified at an ISO/IEC 17025 and ISO 17034 accredited laboratory
Traceable to secondary reference standard from NIST and primary certified reference standard from PTB
Ready-to-use solution
Available in a sealed plastic bottle and sustainable Titripac® packaging for a reduced waste generation
Accompanied with a detailed and batch-specific certificate of analysis (CoA) for an effective audit
Product label follows the ISO Guide 31 and contains information about ordering number, article description, lot number, safety data, and expiry date
Packaging material subjected to comprehensive stability studies as per ISO Guide 35
Legal Information
CERTIPUR is a registered trademark of Merck KGaA, Darmstadt, Germany
Titripac is a registered trademark of Merck KGaA, Darmstadt, Germany