现欲将粗盐提纯,再用制得的精盐配制质量分数一定的氯化钠溶液,

现欲将粗盐提纯,再用制得的精盐配制质量分数一定的氯化钠溶液,下列说法正确的是(  )

A.过滤时玻璃棒轻轻斜靠在单层滤纸一边B.蒸发滤液时,待蒸发皿中滤液蒸干时,即停止加热

C.配制溶液时需要经过计算、称量(量取)、溶解、装瓶等步骤D_________________________

答案

C 过滤时玻璃棒轻轻斜靠在三层滤纸一边

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