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问题 选择题

某同学设计了在实验室制取氧气的六种方案：①只加热氯酸钾  ②只加热高锰酸钾  ③只加热二氧化锰  ④氯酸钾和二氧化锰共热  ⑤氯酸钾和高锰酸钾共热 ⑥电解水．能制取氧气的有（　　）

A．①②④⑤

B．①②④

C．②③④

D．②④⑤

答案

①只加热氯酸钾，反应过慢，一般要用二氧化锰催化，方可完成．

②高锰酸钾在加热条件下生成锰酸钾、二氧化锰和氧气，反应的化学方程式是：2KMnO4

  △  
.
 
K2MnO4+MnO2+O2↑．

③只加热二氧化锰，不能制的氧气．

④氯酸钾在二氧化锰的催化作用下生成氯化钾和氧气，反应的化学方程式为：2KClO3

MnO2
.
△
2KCl+3O2↑．

⑤氯酸钾和高锰酸钾共热时，高锰酸钾分解生成二氧化锰、锰酸钾、氧气，氯酸钾在二氧化锰的作用下也生成氧气．

⑥水在通电条件下分解生成氢气和氧气，反应的化学方程式为：2H2O

 通电 
.
 
2H2↑+O2↑．（生成的气体不易收集，所以不适合实验室制取氧气，所以不可取．）

另外还可以：过氧化氢在二氧化锰的催化作用下生成水和氧气，反应的化学方程式为：2H2O2

 MnO2 
.
 
2H2O+O2↑．

氧化汞加热分解生成汞和氧气，反应的化学方程式是：2HgO

  △  
.
 
2Hg+O2↑．（因为氧化汞受热分解生成液体汞，空气中极易挥发成汞蒸气，而汞蒸气无论是被呼吸还是被皮肤吸附都会引起汞中毒，对人体造成极大损伤．）

所以②④⑤⑥可以生成氧气．在实验室可进行的实验是：②④⑤．

故选D．

阅读理解
阅读理解。
     Anybody running a company knows that a well-planned conference can greatly improve performance of
that business. The main reason for this is that it takes your employees away from the daily workplace and
offers them somewhere fresh for a short time. However, unless the conference is well thought out it will not
have the best results and you will have wasted a great deal of money. Here are some tips for you.
     The first step is to find the right place. Can your employees easily reach the conference center? Is it near
a railway station? Is it close to a good, fast road? Has it plenty of suitable parking space? If you are going to
choose a hotel, then perhaps the hotel has cheaper rates at weekends or, if it is in a popular tourist area,
midweek rates may be cheaper. Furthermore, you need to think whether there is a bathroom. After a day's
meeting, maybe your employees would like to have a hot water bath. Or maybe there are other needs to satisfy
depending on your employees' taste.
     Another important requirement is food and drink. Breakfast is a time when people can relax before work
begins,but you may not want a long break for lunch in the middle of the day. Buffet (自助餐) lunches are very
popular for this reason. Then there is dinner, which most employees consider a reward for a day's hard work! 
     Whatever your needs are, it is essential (基本的) to think ahead if you want a successful conference.
1. In the text the writer is trying to _____.
[ ]
A. complain about a conference center
B. describe a good conference center he has been to
C. persuade employers to choose a suitable place for a conference
D. advise employees where to stay for a conference
2. Readers read the text in order to _____.
[ ]
A. find out about organizing conferences
B. learn how to reward good employees
C. find out about running a business
D. 1earn some details about conference centers
3. What is very important when choosing a conference center?
[ ]
A. Cheap food and drink.
B. Free car parking.
C. Good transport connections.
D. Popular tour areas.
4. Which center would the writer recommend to an employer?
[ ]
A.
                    ★STAR★
                 CONFERENCE 
                     CENTRE
●Close to airport and golf course.
●Choice of conference rooms.
●Swimming pool and sauna.
●3 full meals a day included in price.
B.
                          WATT 
              CONFERENCE CENTRE
●5 Minutes from city center and close to 
  motorway
●Full breakfast, light lunches and exciting 
  dinner menus.
●Choice of accommodation (住宿) to suit
   your financial needs.
C.
            ★Topps Conference center
●Enjoy beautiful scenery high up in the hills.
●Continental breakfast served in bedroom if
  wished.
●Minibus service to nearest town.
D.
                 ★Royal conference Center
●Situated in quiet countryside.
●Free car park available for guests.
●TV and VHS included in your conference
  costs as well as three buffet style meals a day.
                                                                                                                                                         
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单项选择题

有关旁气流通气监测法的叙述哪一项是错误的（）

A.D-lite传感器为其关键部件

B.传感器有两个并列的测压小管和一采样管

C.两个测压小管伸入传感器内，内口指向传感器中心

D.传感器可连接于气管导管处

E.测量准确性不受持续性新鲜气流的影响
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