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问题 计算题

（7分）已知3Cu+8HNO3==3Cu(NO3)2+2NO+4H2O

（1）该反应的还原产物是          。

（2）将化学方程式改写成离子方程式。                                

若有6mole-发生转移，则

（3）被氧化的铜的物质的量为            。

（4）被还原的硝酸的质量是                。

（5）生成的NO在标准状况下的体积为           。.

(6) 已知硝酸溶液的体积为2L，硝酸全部参与反应，则该硝酸的物质的量浓度为           。

答案

（1）  NO （2）3Cu+8H++2NO3-==3Cu2++2NO↑+4H2O 

（3）3mol   （4）126g    （5）44.8L    （6）4mol/L（2分）

（1）氧化剂被含有生成还原产物。硝酸是氧化剂，所以NO是还原产物。

（2）硝酸和硝酸铜属于强电解质，属于反应的离子方程式为

3Cu+8H++2NO3-==3Cu2++2NO↑+4H2O。

（3）根据方程式可知每消耗3mol铜就转移6mol电子，所以若有6mole-发生转移时被氧化的铜是3mol。还原产物是2molNO，所以被还原的硝酸是2mol，质量是2mol×63g/mol＝126g。生成的NO是2mol，体积是2mol×22.4L/mol＝44.8L。参加反应的硝酸是8mol，所以浓度是.

单项选择题

以下叙述中正确的是 ______。

A) C语言的源程序不必通过编译就可以直接运行
B) C语言中的每条可执行语句最终都将被转换成二进制的机器指令
C) C源程序经编译形成的二进制代码可以直接运行
D) C语言中的函数不可以单独进行编译
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单项选择题

Many foreigners who have not visited Britain call all the inhabitants English, for they are used to thinking of the British Isles as England. (1) , the British Isles contain a variety of peoples, and only the people of England call themselves English. The others (2) to themselves as Welsh, Scottish, or Irish, (3) the case may be; they are often slightly annoyed (4) being classified as "English".

Even in England there are many (5) in regional character and speech. The chief (6) is between southern England and northern England. South of a (7) going from Bristol to London, people speak the type of English usually learnt by foreign students, (8) there are local variations.

Further north regional speech is usually " (9) " than that of southern Britain. Northerners are (10) to claim that they work harder than Southerners, and are more (11) They are open-hearted and hospitable; foreigners often find that they make friends with them (12) Northerners generally have hearty (13) : the visitor to Lancashire or Yorkshire, for instance, may look forward to receiving generous (14) at meal times.

In accent and character the people of the Midlands (15) a gradual change from the southern to the northern type of Englishman.

In Scotland the sound (16) by the letter "R" is generally a p sound, and "R" is often pronounced in words in which it would be (17) in southern English. The Scots are said to be a serious, cautious, thrifty people, (18) inventive and somewhat mystical. All the Celtic peoples of Britain (the Welsh, the Irish, the Scots) are frequently (19) as being more "fiery" than the English. They are (20) a race that is quite distinct from the English. (289 words)

Notes: fiery 暴躁的，易怒的。

（20）（）

A.with

B.of

C.among

D.against
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