1.99001

Buffer solution

(potassium hydrogen phthalate), traceable to SRM from NIST and PTB pH 4.01 (25°C) Certipur^®

• Synonym(s): Buffer solution pH 4.01 (25°C) (potassium hydrogen phthalate)
• UNSPSC Code: 12161704
• NACRES: NA.25

Properties

• grade: certified reference material
• Quality Level: 300
• product line: Certipur^®
• pH: 4.0 (25 °C in H₂O)
• application(s): environmental; food and beverages; general analytical; industrial qc; pharmaceutical
• format: mixture
• storage temp.: 10-30°C

Description

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.

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 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

Safety Information

• Storage Class: 12 - Non Combustible Liquids
• wgk_germany: WGK 1
• flash_point_f: Not applicable
• flash_point_c: Not applicable