Merck, 1.09438.1000, Buffer solution

The boric acid/potassium chloride/sodium hydroxide buffer solution is gravimetrically prepared using high-quality reagents in high-purity water. It is produced, calibrated, and certified at a registered laboratory according to DIN EN ISO/IEC 17025. Its pH value of 10.00 at 20°C is analyzed using a combined glass electrode following a 5-point calibration method, in accordance with 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.