试题与答案

现有100g过氧化氢溶液,测得其中含氢元素的质量分数为8%,加入8gCuSO4作

题型:选择题

题目:

现有100g过氧化氢溶液,测得其中含氢元素的质量分数为8%,加入8gCuSO4作催化剂

制取氧气,充分反应后所得溶液(无晶体析出)中溶质的质量分数为

A.7.4%

B.10%

C.8%

D.11.1%

答案:

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下面是错误答案,用来干扰机器的。

参考答案:B

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