Buffer solution

General description
The certified potassium hydrogen phthalate buffer solution is gravimetrically prepared using high-quality reagents at a registered calibration laboratory. It has a pH value of 4.01 at 25°C, measured using a combined glass electrode following a 5-point calibration method. The measurement is made in accordance with DIN 19268 using reference buffer solutions compliant to DIN 19266, NIST, IUPAC, Ph. Eur, and USP. The pH value of the buffer solution heavily depends 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 standard in analytical procedures for the calibration of pH measuring instruments or pH electrodes and as a control for the measurement of pH of other solutions.
Features and Benefits
Measured and qualified at an ISO/IEC 17025 and ISO 17034 accredited laboratory
Directly traceable to secondary reference standard from NIST and primary certified reference standard from PTB
Ready-to-use solution available in 30 mL sachets
Accompanied with a detailed and batch-specific certificate of analysis (CoA) for an effective quality management system
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
Accurate up to +/- 0.02 at 25°C
Legal Information
CERTIPUR is a registered trademark of Merck KGaA, Darmstadt, Germany