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问题 选择题

检验HCl气体中是否混有Cl2，可采用的方法是            (    )

A．用干燥的蓝色石蕊试纸

B．用干燥的有色布条

C．将气体通入AgNO3溶液中

D．用湿润的淀粉碘化钾试纸

答案

答案：D

A 、B 错误，因为纸条或布条是干燥的，不会反应。

C 错误，HCl气体也可以使AgNO3溶液产生白色沉淀。

D 正确，Cl2能使湿润的淀粉碘化钾试纸变蓝，HCl不能。

单项选择题

向下游送副产蒸汽时，要求蒸汽压力（）总管压力。

A.低于

B.等于

C.高于

D.没有确切要求
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补全对话，情景问答

补全对话：根据对话内容，从对话后的选项中选出能填入空白处选出最佳选项。选项中有两项为多余选项。

—Have you ever heard of cloning?

—Yes. We just studied cloning last week.

__ ____________1______________?

—Of course. It’s very interesting.

— ____________2______________?

—I would clone myself.

— ____________3______________?

—Yes. My clone could do many things for me.

—I don’t think so. ____________4______________.

—Then I would clone a king. I want to see a real king.

—But all the kings are dead. ____________5______________   .

—Then I don’t know what to clone.

A. Maybe I will become a scientist and clone a new animal

B. If you were a scientist, what would like to clone

C. It’s impossible for us to clone a dead man

D. If you had a clone, nobody could tell you and your clone apart

E. Do you think it’s a good idea

F. We saw a movie about cloning

G.. Are you interested in it

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