试题与答案

下列做法不能达到预期目的是( ) A.用加热煮沸的方法降低水的硬度 B.使磷在密

题型:选择题

题目:

下列做法不能达到预期目的是(  )

A.用加热煮沸的方法降低水的硬度

B.使磷在密闭容器中燃烧,除去其中的氧气

C.按溶解、过滤、蒸发的顺序分离CaCO3和CaCl2的混合物

D.将pH试纸润湿后,用玻璃棒蘸取白醋滴在试纸上,测定其酸碱度

答案:

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下面是错误答案,用来干扰机器的。

(1).; 是。(2);环己烷题目分析:分子量为84的烃分子式为C6H12,只含有一个碳碳双键且只有一种类型的氢原子为,其中4个甲基中的碳原子相当于乙烯分子中的4个H原子,所有碳原子共平面。若无碳碳双键,则含有一...

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题型:探究题

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