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实验要点一、化学实验基本操作(一) 1.过滤:用于分离液体和不溶性固体。操作过程中一定要做到“一贴、二低、三接触”。“一贴”是指滤纸紧贴漏斗内壁。“二低”是指滤纸边低于漏斗边;滤液液面要低于滤纸边。“三接触”是指烧杯嘴要紧靠玻璃棒使液体沿玻璃棒流入漏斗;玻璃棒下端要靠在三层滤纸一边;漏斗管末端要紧靠烧杯内壁。洗涤沉淀一般用的方法是用
Experimental Points I. Basic Operation of Chemical Experiment (1) 1. Filtration: It is used to separate liquids and insoluble solids. During the operation, you must do one, two, three contacts. “One sticker” means that the filter paper sticks to the inner wall of the funnel. “Second low” means that the edge of the filter paper is below the funnel edge; the liquid level of the filtrate is lower than the edge of the filter paper. “Three contacts” means that the beaker mouth closes the glass rod so that the liquid flows along the glass rod into the funnel; the lower end of the glass rod rests on the side of the three-layer filter paper; the end of the funnel tube is close to the inner wall of the beaker. The general method used for washing sediments is to use