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Reagent grade sodium tungstate, RG sodium tungstate for short, may be applied for precision analysis and scientific research. Reagent-grade chemical substances are labeled red. There are a variety of chemical reagents, so that it is difficult to prepare them into multiple grades or different specifications at the same time. So, it is hard to obtain reagents of the required purity or grade sometimes. And therefore, it is of significance for users to know how to purify reagents. There are many…

99% sodium tungstate’s impurities may be determined using lanthanum hydroxide as coprecipitation agent by inductively coupled plasma atomic emission spectrometry (ICP-AES method) after coprecipitation separation and concentration of these impurities. These trace metal impurities are calcium, tin, cobalt, copper, iron, manganese, zinc, and nickel, etc. The determination of trace metal impurities must be performed on a high resolution spectrometer if the ICP-AES method is adopted directly. That is because the matrix tungsten often has severe spectral overlap interference with the…

Sodium tungstate is a kind of white shiny crystalline or crystalline powder, whose chemical formula is Na2WO4. It is weathered in the air. Also, it is insoluble in ethanol, slightly soluble in ammonia, and soluble in water, which is slight alkalinity. It is also known for its anti-diabetic effects. Sodium tungstate is prepared from tungsten ores used to manufacture tungsten by reducing it. It is used as catalyst for epoxidation of alkenes and oxidation of alcohols into aldehydes or ketones…