含水量的划分

顺⑦.zì繎.

网上看到卡尔费休水分测定方法里有“含水量高的物质，含水量低的物质，吸湿性物质”等，请教一下这里含水量高低是怎么划分的？

beiwei5du

这个应该是称量准确度和测量准确度的平衡吧！

beiwei5du

KF has a high accuracy and precision, typically within 1% of available water, e.g. 3.00% appears as 2.97 - 3.03%. Although KF is a destructive analysis, the sample quantity is small and is typically limited by the accuracy of weighing. For example, in order to obtain an accuracy of 1% using a scale with the typical accuracy of 0.2 mg, the sample must contain 20 mg water, which is e.g. 200 mg for a sample with 10% water. For coulometers, the measuring range is from 1-5 ppm to ca. 5%. Volumetric KF readily measures samples up to 100%, but requires impractically large amounts of sample for analytes with less than 0.05% water.仅供参考！
https://en.wikipedia.org/wiki/Karl_Fischer_titration