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问题 填空题

某化学反应2AB＋D在四种不同条件下进行。B、D起始浓度为0。反应物A的浓度（mol·L－1）随反应时间（min）的变化情况如下表：

实验序号 0102030405060
1800℃1．00．800．670．570．500．500．50
2800℃c20．600．500．500．500．500．50
3800℃c30．920．750．630．600．600．60
4820℃1．00．400．250．200．200．200．20
  根据上述数据，完成下列填空：

（1）在实验1中，反应在10至20分钟内平均速率为                              。

（2）在实验2中，A的初始浓度c2＝______               ____，反应经20分钟就达到平衡，可推测实验2中还隐含的条件是______     ____。

（3）设实验3中的反应速率为v3，实验1的反应速率为v1，则v3__________v1（填“＞”、“＝”或“＜”），且c3__________1．0mol·L－1（填“＜”、“＝”或“＞”）。

（4）比较实验4和实验1，可推测该反应是__________反应（填“吸热”或“放热”）。

答案

（1）0．013 mol/（L·min） （2分）      

（2）1．0 mol/L （2分）催化剂（2分）

（3） ＞ ＞（各1分）              

（4）吸热（2分）

填空题

显微镜下呈矛头状，钝端相对成双排列的革兰阳性菌是（）。
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单项选择题

Now which are the animals really to be pitied in captivity First, those clever beings whose lively urge for activity can find no outlet behind the bars of the cage. This is most conspicuous, even for the uninitiated, in the case of animals which, when living in a free state, are accustomed to roaming about widely. Owing to this frustrated desire, foxes and wolves housed, in many old-fashioned zoos, in cages which are far too small, are among the most pitiable of all caged animals.
Though pinioned swans generally seem happy, under proper care, by hatching and rearing their young without any trouble, at migration time things become different: they repeatedly swim to the lee side of the pond, in order to have the whole extent of its surface at their disposal, trying to take off. Again and again the grand preparations end in a pathetic flutter of their half wings ; a truly sorry picture !
This, however, rarely awakens the pity of the zoo visitor, least of all when such an originally highly intelligent and mentally alert animal has deteriorated, in confinement, into a crazy idiot, a very caricature of its former self. Sentimental old ladies, the fanatical sponsors of the societies for Prevention of Cruelty to Animals, have no compunction in keeping a grey parrot in a relatively small cage or even chained to a perch. Together with the large corvines, the parrots are probably the only birds which suffer from that state of mind, common to prisoners, namely, boredom.

According to the author in Paragraph 1, what animals suffer most in captivity

A. Climbing animals.
B. Hunting animals.
C. Parroting animals.
D. Singing animals.
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