General description
It is a solid standard prepared gravimetrically from high-purity reagents. The water content of it is determined by coulometric Karl Fischer oven method at 170°C with an extraction time of 600 seconds. Additionally, its measured water content is verified by thermogravimetric analysis. Unlike other solid standards such as tartrate, lactose, or citrate, the water standard oven 1% has significantly lower water content and can be used over a broad temperature range of 150°C to 400°C due to its inorganic composition. It is characterized in accredited quality control (QC) laboratory according to DIN EN ISO/IEC 17025.
Please visit ISO certificates and Site Quality Self-Assessments to access the current certificates of accreditation.
In our effort to be more sustainable, we′re going digital with COAs-download them directly from our website. Download your certificate at https://www.sigmaaldrich.com/US/en/documents-search to view certified values, including uncertainty and expiry date.
Application
Water standard oven 1% is used as certified reference material to check the accuracy of coulometric and volumetric water determinations, according to ISO 9001 chapter 7.1.5 “Monitoring and measuring resources”, using Karl Fischer oven and thermobalances. But its low water content of 1% makes it particularly suitable for water determinations using Karl Fischer oven with a coulometer.
Features and Benefits
Packed in convenient glass bottles with the material subjected to stability and homogeneity studies following ISO 17034 and ISO Guide 35
Supplied with a batch-specific digital certificate of analysis (CoA) having data on exact measured water, uncertainty, method of analysis, measuring method, and minimum shelf life
Characterized in an ISO/IEC 17025 and ISO 17034 accredited calibration laboratory
Directly traceable to SI unit (kg)
Other Notes
Replaces: 1.88054.0005
Legal Information
AQUASTAR is a registered trademark of Merck KGaA, Darmstadt, Germany

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