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问题 选择题

某化学小组研究在其他条件不变时，改变密闭容器中某一条件对A2(g)+3B2(g)2AB3(g)化学平衡状态的影响，得到如下图所示的曲线（图中T表示温度，n表示物质的量）下列判断正确的是

A．若＞，则正反应一定是放热反应

B．达到平衡时的转化率大小为：b＞a＞c

C．若＞，达到平衡时b、d点的反应速率为＞

D．在和不变时达到平衡，的物质的量大小为：c＞b＞a

答案

答案：D

题目分析：A、若T2＞T1，由图象可知温度升高生成物的物质的量增大，说明升高温度平衡向正反应分析移动，则正反应为吸热反应，故A错误。B、根据图象可知，a、b、c各点中B的起始物质的量依次增大，对于可逆反应来说，增大一种反应物的物质的量或浓度，有利于平衡向正反应方向移动，则另一种反应物的转化率增大，则达到平衡时A2的转化率大小为：a＜b＜c，故B错误；C、温度越高速率越快，温度T2＞T1，达到平衡时b、d点的反应速率为vd＜vb，故C错误；对于可逆反应来说，增大一种反应物的物质的量或浓度，有利于平衡向正反应方向移动，生成物的物质的量增多，所以达到平衡时，AB3的物质的量大小为c＞b＞a，故D正确；

单项选择题

结肠破裂

A．腹膜炎出现早
B．腹膜炎严重，呈板状腹
C．腹膜炎出现较晚，但较重
D．腹膜炎出现较晚且较轻
E．无腹膜刺激征
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单项选择题

It is quite reasonable to blame traffic jams, the cost of" gas and the great speed of modern life, but manners on the toad are becoming horrible. Eye,body knows that the nicest men would become fierce tigers behind the wheel. It is all right to have a tiger in a cage, but to have one in the driver’s seat is another matter.
Road politeness is not only good manners, but good sense too. It takes the most cool-headed drivers great patience to give up the desire to beat back when forced to face rude driving. On the other hand, a little politeness goes a long way towards reducing the possibility of quarrelling and fighting. A friendly nod or a wave of thanks in answer to an act of politeness helps to create an atmosphere of good will and calmness so necessary in modern traffic conditions. But such behaviors of politeness are by no means enough. Many drivers nowadays don’t even seem able to recognize politeness when they see it.
However, misplaced politeness can also be dangerous. Typical examples are the driver who waves a child crossing the street at a wrong place into the path of oncoming cars that may be not able to stop in time. The same goes for encouraging old ladies to cross the road wherever and whenever they want to.
An experienced driver, whose manners are faultless, told me it would help if drivers learnt to correctly join in traffic stream without causing total blockages that give rise to unpleasant feelings. Unfortunately, modern drivers can’t even learn to drive,let alone master the roadmanship. Years ago, experts warned us that the fast increase of the car ownership would demand more give-and-take from all road users. It is high time for all of us to take this message to heart.

The following statements are right EXCEPT that______.

A. some modern drivers are not good at driving
B. road politeness is good sense as well as good manners
C. it is also right to have a tiger in the driver’s seat
D. a friendly driver should nod or wave thanks in answer to an act of politeness
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