Buffer solutions

General description
A set of 3 certified buffer solutions of pH 4.01(phthalate), 7.00 (phosphate), and 10.00 (borate)? gravimetrically prepared at a registered calibration laboratory with high-quality reagents and water. The pH values of the buffers are measured using a combined glass electrode, following a 5-point calibration method. The measurements are made following DIN 19268 using reference buffer solutions compliant to DIN 19266, NIST, IUPAC, Ph. Eur, and USP. The pH values are strongly dependent on the temperature and therefore a constant temperature must be maintained during their use.
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Download your certificate at http://www.sigma-aldrich.com to view certified values, including uncertainty and expiry date.
Application
They are used as standards to calibrate pH measuring instruments or pH electrodes and as controls to measure the pH of other solutions.
Features and Benefits
Measured and qualified at an ISO/IEC 17025 and ISO 17034 accredited laboratory
Traceable to secondary reference standards from NIST and primary certified reference standards from PTB
Ready-to-use solutions available in 30 mL sachets
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
pH 4.00 and pH 6.99 buffer CRMs in the pack are accurate upto +/- 0.02 at 25 °C and the pH 10.01 buffer CRM is accurate upto +/-0.03 at 25 °C
Legal Information
CERTIPUR is a registered trademark of Merck KGaA, Darmstadt, Germany