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问题 实验题

（7分）实验室可以用草酸（H2C2O4）在浓硫酸的作用下来制取一氧化碳，反应原理为：

H2C2O4CO↑+ CO2↑+ H2O

小明同学设计下图所示装置来制取一氧化碳，并验证一氧化碳的性质。   

请回答下列问题：

（1）长颈漏斗a的漏斗颈没入液面下的目  

的是                       。

（2）B中氢氧化钠溶液的作用是                           。

（3）C中澄清石灰水的作用是                                                 。

（4）通过什么现象可以判断CO能与CuO反应？                                               。

（5）D中反应的化学方程式是                                                 。

答案

（1）防止气体从漏斗逸出（1分）   （2）吸收二氧化碳（1分）

（3）检验二氧化碳是否被完全吸收（1分）

（4）D中黑色粉末变为红色，E中石灰水变浑浊。（2分）

（5）CuO + CO  Cu + CO2（2分）

题目分析：（1）长颈漏斗a的漏斗颈没入液面是为了让液体封住导管口，防止气体从漏斗逸出。

（2）根据题意可知：A中反应会生成CO、 CO2，而在装置E需要验证D中会反应生成二氧化碳气体，所以应将A中生成的二氧化碳气体利用B中氢氧化钠溶液除去。

（3）C中澄清石灰水的作用是检验二氧化碳是否被完全吸收。

（4）如D中黑色粉末变为红色，E中石灰水变浑浊；则说明有还原性的物质与氧化铁反应且生成二氧化碳，则可说明CO能与CuO反应。

（5）氧化铜和一氧化碳反应会生成铜和二氧化碳，反应的化学方程式是CuO + CO  Cu + CO2。

选择题

如图，已知AC=AD，BC=BD，那么

[ ]

A．CD垂直平分AB

B．AB垂直平分CD

C．CD与AB互相垂直平分

D．以上都不对

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单项选择题

Passage Three

Successful businesses tend to continue implementing the ideas that made them successful. But in a rapidly changing world, ideas often become obsolete overnight. What worked in the past won’t necessarily work in the future. In order to thrive in the future, you must constantly create new ideas for every aspect of your business. In fact, you must continually generate new ideas just to keep your head above water. Businesses that aren’t creative about their future may not survive.
Although Bill Gates is the richest, most successful man on the planet, he did not anticipate the Internet. Now he’s scrambling to catch up. If Bill Gates can miss a major aspect of his industry, it can happen to you in your industry. Your business needs to continually innovate and create its future. Gates is now constantly worried about the future of Microsoft. Here’s what he said in a recent interview in U.S. News World Report: "Will we be replaced tomorrow No. In a very short time frame, Microsoft is an incredibly p company. But when you look to the two-to-three-year time frame, I don’t think anyone can say with a straight face that any technology company has a guaranteed position. Not Intel, not Microsoft, not Compaq, not Dell, take any of your favorites. And that’s totally honest."
You may remember that in 1985 the Cabbage Patch Kids dolls were the best-selling toy on the market. But after Coleco Industries introduced their sensational line of dolls they became complacent and didn’t create any new toys worth mentioning. As a result, Coleco went bankrupt in 1988.
The most successful businesses survive in the long term because they constantly reassess their situations and reinvest themselves accordingly. The 3M Company has a 15% rule: employees are encouraged to spend 15% of their time developing new ideas on any project they desire; it’s no surprise, then, that 3M has been around since 1902.
Most businesses are not willing to tear apart last year’s model of success and build a new one. Here’s a familiar analogy to explain why they are lulled into complacency: imagine that your business is like a pot of lobsters; to cook lobsters, you put them into a pot of warm water and gradually turn up the heat; the lobsters don’t realize they’re being cooked because the process is so gradual. As a result, they become complacent and die without a struggle. However, if you throw a lobster into the pot when the water is boiling, it will desperately try to escape. This lobster is not lulled by a slowly changing environment. It realizes instantly that it’s in a bad environment and takes immediate action to change its status.

Coleco Industries’ case suggests that ______.

A．the Cabbage Patch Kids dolls were the best-selling toy on the market

B．the Cabbage Patch Kids dolls are sensational line of dolls

C．complacency and lack of creation will ultimately ruin a business

D．the most successful businesses survive in the long term
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