(10镇江24).(4分)某兴趣小组进行粗盐提纯并配制NaCl溶液,请回

(10镇江24).(4分)某兴趣小组进行粗盐提纯并配制NaCl溶液,请回答下列问题:

 

 

(1)操作①、②、③依次为下图中的(填字母)          

 

 

 

(2)若NaCl的产率偏低( ),则可能的原因是(填字母)

 

A.过滤时滤纸有破损          

B.蒸发时有固体溅出

C.溶解含有泥沙的粗食盐时,加入的水量不足

(3)用上述实验所得NaCl晶体配制5%NaCl溶液50.0g,需称取NaCl     g,配制时需要的玻璃仪器有烧杯、玻璃棒、滴管、     

 

答案

(1)C B A(1分,顺序错不给分)

(2)B C(1分,单选B或C,给0.5分, 选A B、A C、不给分,选A B C给0.5分)

(3)2.5(1分)    量筒(1分)

解析:略

 

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