主题：【讨论】库仑水分仪 校验

折算一下理论含水量。

直接拿微量注射器注水，查看结果。

原文由 面对面想你(jackcong) 发表:
直接拿微量注射器注水，查看结果。

加水的质量是多少呢，有什么依据没？

楼主使用的是哪个牌子的水分测定仪呢

SCHOTT牌的

原文由 xkcpu(xkcpu) 发表:

原文由 面对面想你(jackcong) 发表:
直接拿微量注射器注水，查看结果。

加水的质量是多少呢，有什么依据没？

美国药典：

For determination of trace amounts of water (less than 1%), it is preferable to use Reagent with a water equivalency factor of not more than 2.0. Sodium tartrate may be used as a convenient water reference substance. Quickly add 75 to 125 mg of sodium tartrate (C4H4Na2O6·2H2O), accurately weighed by difference, and titrate to the endpoint. The water equivalence factor F, in mg of water per mL of reagent, is given by the formula:

2(18.02/230.08)(W/V)

in which 18.02 and 230.08 are the molecular weights of water and sodium tartrate dihydrate, respectively; W is the weight, in mg, of sodium tartrate dihydrate; and V is the volume, in mL, of the Reagent consumed in the second titration.

For the precise determination of significant amounts of water (1% or more), use Purified Water as the reference substance. Quickly add between 25 and 250 mg of water, accurately weighed by difference, from a weighing pipet or from a precalibrated syringe or micropipet, the amount taken being governed by the reagent strength and the buret size, as referred to under Volumetric Apparatus [img=12,20]mk:@MSITStore:E:\药典\USP\usp32_nf27_2009_roydan.chm::/pub/data/images/chars/lang.gif[/img]31[img=12,20]mk:@MSITStore:E:\药典\USP\usp32_nf27_2009_roydan.chm::/pub/data/images/chars/rang.gif[/img]. Titrate to the endpoint. Calculate the water equivalence factor, F, in mg of water per mL of reagent, by the formula:

W/V

in which W is the weight, in mg, of the water; and V is the volume, in mL, of the reagent required.
中心意思是：
对于样品中要求水含量小于1%的，取75~125mg的酒石酸钠(C4H4Na2O6·2H2O)进行标定；
对于样品中要求水含量大于等于1%的，取25~250mg的水进行标定

你取50ul水，直接注入到反应槽中，然后立即封禁盖子，将样品质量设置为1g，查看测试结果是否为【（50*0.000001*1000）/1】*100%