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问题 选择题

A、B、C、D四种物质皆易溶于水，且在水溶液中存在如下化学平衡，加水稀释后，平衡向正反应方向移动的是……（ ）

A、A+BC+D     B、A+H2OC+D     C、A+BC+H2O     D、A+2B+H2OC

答案

答案：B

首先注意到所加水属于纯液体，固体和纯液体的量的增减对化学平衡移动是没有影响的，但加水可以改变其它物质的浓度，从而影响化学平衡。A选项，加水稀释A、B、C、D均为相同倍数，故平衡不移动。B选项，A与C、D各稀释相同倍数，C、D为生成物两种浓度的减小，大于A物质（反应物）浓度的减小，利用勒夏特列原理，平衡右移。同样道理，C、D两个选项，平衡均左移。

单项选择题

44，31，45，30，46，( )

A．47

B．29

C．48

D．28
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阅读理解

Last week, Mrs.Milly went to London. She does not know London very well, and she lost her way. Suddenly, she saw a man near a bus stop. “I can ask him the way,”she said to herself. “Excuse me, ”she said . “Can you tell me the way to King Street, please?” The man smiled happily. He did not understand English! He is a tourist.   

Then he put his hand into his pocket ( 口袋 ), and took out a phrasebook (常用语手册). He opened the book and found a phrase. He read the phrase slowly. “I am sorry,” he said. “I do not speak English.”

根据文章判断正误.(正确的写A,错误的写 B  ,文章未提到的写NM)

小题1:Mrs Milly went to London last week.

小题2:Mrs Milly asked a man the way to a bus stop.

小题3:The man didn’t know the way to King Street.

小题4:The man was a tourist and he knew English well.

小题5:The phrasebook was in the hand of the man.
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