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化学除杂问题主要是考查学生对元素化合物重要性质的掌握,及其相互转化关系的理解.现对此类问题总结如下.一、物理方法物理除杂法是利用杂质与被提纯物质之间物理性质的差异而除去杂质的方法.1.溶解、过滤法.把不溶于液体的固体和液体分离或是把可溶性固体和难溶性固体分离的方法.2.结晶法.该方法适用于分离可溶性混合物或除去可
Chemical impurity removal is mainly to examine the students master the important properties of the elemental compounds, and their understanding of the relationship between the transformation of these problems are summarized as follows: First, the physical method Physical impurity removal is the use of impurities and purification of physical substances The nature of the differences in the removal of impurities 1. Dissolution, filtration method. The liquid-insoluble solids and liquid separation or separation of soluble solids and insoluble solids. 2. Crystallization method. This method is suitable for the separation of soluble mixture Or remove it