用400克溶质的质量分数为20%的NaCl溶液，配制成10%的NaCl溶液，需加水的质量为_刷题宝

题干

用400克溶质的质量分数为20%的NaCl溶液，配制成10%的NaCl溶液，需加水的质量为（）

A：100 g

B：200g

C：400 g

D：800g

上一题下一题 0.0难度选择题更新时间:2014-09-29 03:25:22

答案(点此获取答案解析）

C

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