物质检验时,首先对试样进行外观观察,试样的外观主要是指_________

物质检验时,首先对试样进行外观观察,试样的外观主要是指______________________;若试样是固体时,应先取少量配成溶液,并注意试样是易溶还是___________、___________,有无浑浊或在溶解过程中有无___________产生;在检验时,试剂用量每次应取___________。

答案

状态、颜色  微溶  难溶  气体  少量

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