问题 选择题

在温度相同,压强分别为p1和p2的条件下,发生反应:

A(气)+2B(气)nC(气)

式中C的百分含量与时间t的曲线如下图所示。下面的结论正确的是

A.p1>p2 n<3

B.p1<p2 n>3

C.p1<p2 n=3

D.p1>p2 n>3

答案

答案:D

从两个曲线可看到,达平衡所需要的时间是p1比p2所需的时间少,因为t1<t2压强增大(即浓度增大),反应速度也变大,所以p1大于p2。故B、C错误。

由平衡时的C%来看,p2时的值大于p1时的值。即在p2时比在p1时更有利于C的生成。由于p1>p2,说明上式的正反应为气体体积增大的反应。这就表明n值应大于1+2。故D正确。

阅读理解

阅读理解

    Several years ago, a television reporter was talking to three of the most important people in America.

One was a very rich banker, another owned one of the largest companies in the world, and the third

owned many buildings in the center of New York.

    The reporter was talking to them about being important.

    "How do we know if someone is really important?" the reporter asked the banker.

    The banker thought for a few moments and then said, "I think anybody who is invited to the White

House to meet the President of the United States is really important."

    The reporter then turned to the owner of the very large company. "Do you agree with that?" she

asked.

    The man shook his head, "No, I think the President invites a lot of people to the White House. You'd

only be important if while you were visiting the President, there was a telephone call from the president

of another country, and the President of the US said he was too busy to answer it."

    The reporter turned to the third man. "Do you think so?"

    "No, I don't," he said. "I don't think that makes the visitor important. That makes the President

important."

    "Then what would make the visitor important?" the reporter and the other two men asked.

    "Oh, I think if the visitor to the White House was talking to the President and the phone rang, and the

President picked up the receiver, listened and then said, 'It's for you.' "

1. This story happened in______.

A. England        

B. America        

C. Japan        

D. Australia

2. There are______ in this passage.

A. two men and two women              

B. three men and one woman

C. three women and one man              

D. four women

3. The banker thought______.

A. he was really important because he was a rich banker

B. the visitor to the White House to meet the President of the U.S was really important

C. the visitor who met the President of the US

D. the reporter was really important

4. The owner of the very large company thought______.

A. she was really important because she owned one of the largest companies

B. the banker was really important

C. the owner of many buildings in the center of New York was really important

D. the visitor would be really important if while he was visiting the President.the President would not

answer any telephone call

5. The owner of many buildings thought______.

A. he was really important because he owned many buildings in the center of New York

B. the owner of the very large company was really important

C. the visitor was really important if he was talking to the President and the President received a

telephone call for the visitor

D. the person who worked in the White House was really important

单项选择题