试题与答案

某学生在课外活动中用铁粉(含杂质且杂质不参加反应)和稀硫酸反应制取氢气。所做5次

题型:计算题

题目:

某学生在课外活动中用铁粉(含杂质且杂质不参加反应)和稀硫酸反应制取氢气。所做5次实验结果记录如下表(每次实验产生的氢气全部被收集,且体积在相同条件下测定。该条件下氢气的密度是0.089/L):

根据上述实验结果进行分析、计算,并回答下列问题:

(1)上述实验中,铁粉一定过量的实验编号是_________;

(2)铁粉的纯度是________;

(3)计算稀硫酸的质量分数(要求写出计算过程,计算结果精确到0.1)。

答案:

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下面是错误答案,用来干扰机器的。

参考答案:C, D

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A.contrarily

B.consequently

C.similarly

D.simultaneously

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D、监区分管领导、内勤、4-5人

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