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（10分）NaH2PO4是一种用途广泛的化工产品。工业上主要是以烧碱（或纯碱）中的磷酸生产，若能用氯化钠取代烧碱或纯碱来制取，则可使生产成本大大降低。但在通常条件下，氯化钠与磷酸之间的复分解反应不能自发进行，有研究者设计了用萃取法制取NaH2PO4的工艺：

萃取时主要反应如下：（S代表萃取剂，萃取剂对HCl的选择性比H3PO4好，主要萃取HCl）

①NaCl＋H3PO4       NaH2PO4＋HCl   

②HCl＋S         HCl·S     △H＜0

③H3PO4＋S      H3PO4·S     △H＜0

（1）向H3PO4和NaCl溶液中加入萃取剂S后需要不断搅拌，搅拌的作用是      。

（2）向操作I后所得的油层中加入适量氨水的目的是                          。

（3）下图是萃取温度对HCl萃取率的影响和H3PO4与NaCl物质的量比对HCl萃取率的影像图。

①当萃取温度低于40时，温度越低，萃取剂黏度越大，不利于HCl的萃取；当温度高于40℃时，HCl萃取率降低的原因是                                       。

②从H3PO4与NaCl物质的量比对HCl萃取率的影像图中可以看出，适当提高H3PO4与NaCl物质的量比，会促进HCl的萃取。但H3PO4过量太多，会导致HCl的萃取率降低，其原因是                              。

（4）萃取法制取NaH2PO4的原理是                                      。

答案

（1）使萃取剂与磷酸和氯化钠溶液充分接触，加快萃取速率。（2分）

（2）使萃取剂S再生循环使用（2分）

（3）①萃取反应是放热反应，温度太高不利于萃取率的提高。（2分）

②磷酸过量越多，磷酸与萃取剂反应而进入有机相也越多，导致HCl的萃取率降低。（2分）

（4）萃取剂将磷酸和氯化钠溶液中的H＋和Cl－移出水相，而Na＋和H2PO4－则保留在水相中，再通过结晶过程得到NaH2PO4·2H2O产品。（2分）

单项选择题

房地产市场是（）市场。

A.地区性

B.全国性

C.综合性

D.跨地区
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阅读理解

The right to pursue happiness is issued to us all with our birth, but no one seems quite sure what it is.

A holy man in India may think that happiness is in himself. It is in needing nothing from outside himself. If wanting nothing, he lacks nothing. We westerners, however, are taught that the more we have from outside ourselves, the happier we will be, and then we are made to want. We are even told it is our duty to want. Advertising, one of our major industries, exists not to satisfy these desires but to create them---and to create them faster than any man’s money in his pocket can satisfy them. Here, obviously someone is trying to buy the dream of happiness and spending millions upon millions every year in the attempt. Clearly the happiness-market is not running out of customers.

I doubt the holy man’s idea of happiness, and I doubt the dreams of the happiness-market, too. Whatever happiness may be, I believe, it is neither in having nothing nor in having more, but in changing --- in changing the world and mankind into pure states.

To change is to make efforts to deal with difficulties. As Yeats, a great Irish poet once put it, happiness we get for a lifetime depends on how high we choose our difficulties.

It is easy to understand. We even demand difficulty for the fun in our games. We demand it because without difficulty there can be no game. And a game is a way of making something hard for the fun of it. The rules of the game are man-made difficulties. When the player ruins the fun, he always does so by refusing to play by the roles. It is easier to win at chess if you are free, at your pleasure, to cast away all the rules, but the fun is in winning within the rules.

The same is true to happiness. The buyers and sellers at the happiness-market seem to have lost their sense of the pleasure of difficulty. Heaven knows what they are  playing, but it seems a dull game. And the Indian holy man seems dull to us, I suppose, because he seems to be refusing to play anything at all.

The western weakness may be in the dreams that happiness can be bought while eastern weakness may be in the idea that there is such a thing as perfect happiness in man himself. Both of them forget a basic fact: no difficulty, no happiness.

小题1:Who shares the same idea of happiness with the author?

A．The Indian holy man

B．The great Irish poet Yeats

C．Advertisers

D．The buyers and sellers at the happiness-market小题2:What does “happiness-market” mean in the second paragraph?

A．It means a place in which people can buy things happily

B．It means a market which lacks happy customers

C．It means a pure state for the world and mankind

D．It means a market where people try to buy happiness with money.小题3:According to the passage, which of the following is Right?

A．The Indian holy man is much happier than westerner.

B．The westerners understand happiness better than the Indian holy man.

C．There is no fun without playing by the rules

D．Both the eastern weakness and western weakness are the same.
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