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中考命题中酸碱盐的除杂是化学考查的热点之一。学习过程中,要注重物质的物理性质、化学性质等。题目中常常出现气体混合物除杂,溶液中混合物除杂,固体混合物除杂等。除杂时根据原物质和杂质的性质选择适当的除杂剂和分离方法。所谓除杂,是指除去杂质,同时被提纯物质不得改变。除杂质时至少要满足两个条件:(1)加入的试剂
In the senior high school entrance examination of acid-base salt impurity removal is one of the hottest chemical examination. Learning process, we must pay attention to the physical properties of the material, chemical properties. Often appear in the title gas mixture impurity removal, the mixture of impurities in the solution, the solid mixture impurity and so on. According to the nature of the original substances and impurities when removing impurities select the appropriate method of removing impurities and separation. The so-called impurity, refers to the removal of impurities, at the same time be purified substances can not be changed. At least two conditions must be satisfied when removing impurities: (1) Reagent added