题干

信息时代产生的大量电子垃圾对环境构成了极大的威胁.某“变废为宝”学生探究小组将一批废弃的线路板简单处理后,得到红色金属M和金属E并进行如下框图所示转化,获得高效净水剂K2EO4.

(答题时,化学式及化学方程式中的M、E均用所对应的元素符号表示):

(1)写出M溶于稀H2SO4和H2O2混合液的离子方程式:____ .

(2)检验X中阳离子的方法和现象是____ .

(3)某同学取X的溶液在空气中放置后,酸化并加入KI和淀粉溶液,溶液变为蓝色.写出与上述变化过程相关的离子方程式: ____  、 ____ .

(4)由MSO4的蓝色溶液经一系列操作可以获得蓝色晶体,这些操作中用到的实验仪器除了酒精灯、蒸发皿、铁架台外,还需要用到的玻璃仪器有____ (填写仪器名称).

(5)某同学利用H2还原MO来测定M的相对原子质量,如图是测定装置示意图,A中试剂是盐酸.

①仪器B中应装入____ ,装置D的作用____ ;

②连接好装置并检验装置的气密性后,应首先“加热反应管E”还是“从A瓶中逐滴加入液体”?____ 

在这两步之间还应进行的操作是____ .

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答案(点此获取答案解析)

Cu+H2O2+2H+=Cu2++2H2O,\u53d6X\u6eb6\u6db2\u5c11\u8bb8\u4e8e\u8bd5\u7ba1\u4e2d\uff0c\u6ef4\u5165\u51e0\u6ef4KSCN\u6eb6\u6db2\uff0c\u6eb6\u6db2\u4e0d\u663e\u7ea2\u8272\uff0c\u518d\u5411\u8bd5\u

同类题1

阅读短文,完成表格

    Read the passage carefully and complete the table with only one word for each blank.

    Back in the twentieth century, robots seemed to have a big future, at least in the movies. Like the robots servants in the Star War movies. It looked as if one day robots would do all the boring or dangerous jobs while the humans sat around doing something more interesting. But people were also frightened that robots might become the bosses, not the servants.

    Has it happened? You're still unlikely to see a robot walking around your town but that doesn't mean they don't exist. Robots are used in car making, and in areas which are dangerous for humans, in bomb producing and deep-sea discovering, for example. We employ robots instead of doing the job ourselves. According to the report, there are 750,000 working robots in the world today.

    These working robots definitely look like machines but many scientists are now trying to make robots look more similar to humans. So what will robots be able to do by the year 2030? There are already plans to use robots in hospitals and old people's homes. Robot nurses will remind patients to take their medicine or tell a doctor if the patient needs attention. But many people are worried about the idea of robots looking after the old, the sick and the very young, separating them from important human contact. It may also create unemployment. It is really possible that robots will be used for many jobs in areas.

    But can we be sure that the next generation robots will always follow human orders? Or even destroy them? Or will we be able to create robots with emotions? Only the future will tell.

Will robots ____ the world?

The imagination of robots in the past

The images of robots appeared in movies.

Robots were thought to work for people.

People have a____ that robots would become bosses.

The use of robots at present

Robots don't take over the world.

They ____ people in some dangerous areas, from car making to deep-sea discovering.

People's plans and ____ about robots for the future

Robots will be more like humans.

They will be used in more areas, like in the hospital.

It may cause problems, like the ____ of humans from each other and the unemployment.