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Water Standard Oven 1%

Certified Reference Material for KF oven method Aquastar®


certified reference material

Quality Level


ISO 17025, 17034

product line





Karl-Fischer titration: suitable
titration: suitable

bulk density

460 kg/m3



storage temp.


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 following ISO 760. 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.
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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 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)


Replaces: 1.88054.0005

Legal Information

AQUASTAR is a registered trademark of Merck KGaA, Darmstadt, Germany

Storage Class Code

13 - Non Combustible Solids



Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Certificates of Analysis (COA)

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