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1.概述发射光谱法可以同时测定纯银及其化合物中的多个杂质元素。若先将待测元素与银分离,可以降低分析下限。通常的分离方法有沉淀及共沉淀,萃取和层析法等。将银沉淀成氯化银使其与待测元素分离较为简便。将银沉淀成氯化银,文献认为,Pb、Hg(I)、Tl(I)及Cu(I)溶解度小,Bi及Sb因水解不能分离外,银几乎能与所有的金属阳离子分离;将Hg(I)、Tl(I)、Cu(I)氧化成高价,AgCl溶于氨溶液中,再用盐酸重新沉淀,可使它们与银分离。
1. Overview Emission spectrometry allows the simultaneous determination of multiple impurities in pure silver and its compounds. If the first test element and silver separation, you can reduce the analysis of the lower limit. The usual separation methods are precipitation and coprecipitation, extraction and chromatography. The silver precipitated silver chloride to be separated from the test element is relatively simple. The silver is precipitated into silver chloride, the literature that the solubility of Pb, Hg (I), Tl (I) and Cu (I) small, Bi and Sb can not be separated due to hydrolysis, the silver can be separated from almost all the metal cations; Hg (I), Tl (I) and Cu (I) are oxidized to high prices, AgCl is dissolved in ammonia solution, and then reprecipitated with hydrochloric acid to separate them from silver.