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问题 填空题

2006年12月我市某乡镇为部分居民更换了旧自来水铁质管道，基本解决了管内生锈、饮用水含铁量超标的问题．请回答：

（1）下列与铁质管道生锈有关的物质是______（填代号）．①水        ②氧气       ③氮气

（2）请写出一种防止铁制品生锈的方法______．

（3）某课外小组截取一小段旧铁质管道作样品，与过量的稀盐酸充分反应，则反应后的溶液中含有的溶质是______

A、HCl和FeCl2     B、HCl      C、HCl和FeCl3     D、HCl、FeCl2和FeCl3．

答案

（1）铁在有水和氧气并存时易生锈，铁的生锈与水氧气有关，故填：①②；

（2）在铁制品表面刷漆可以防锈，故填：刷漆；

（3）铁能与盐酸反应生成氯化亚铁和氢气，氧化铁能与盐酸反应生成氯化铁和水，盐酸剩余，故溶液中的溶质有氯化铁、氯化亚铁和硫化氢，故选D．

单项选择题

People are indulging in an illusion whenever they find themselves explaining at a cocktail (鸡尾酒) party, say, that they are "in computers," or "in telecommunications," or "in electronic funds transfer". The implication is that they are part of the high-tech world. Just between US, they usually aren’t. The researchers who made fundamental breakthroughs in those areas are in a high-tech business. The rest of us are (71) of their work. We use computers and other new technology components to develop our products or to organize our affairs. Because we go about this work in teams and projects and other tightly knit working groups(紧密联系在一起的工作小组), we are mostly in the human communication business. Our successes stem from good human interactions by all participants in the effort, and our failures stem from poor human interactions.

The main reason we tend to focus on the (72) rather than the human side of the work is not because it’s more (73) , but because it’s easier to do. Getting the new disk drive installed is positively trivial compared to figuring out why Horace is in a blue funk (恐惧) or why Susan is dissatisfied with the company after only a few months. Human interactions are complicated and never very crisp (干脆的, 干净利落的) and clean in their effects, but they matter more than any other aspect of the work.

If you find yourself concentrating on the (74) rather than the (75) , you’re like the vaudeville character (杂耍人物) who loses his keys on a dark street and looks for them on the adjacent street because, as he explains, "The light is better there!".

（75）处应填（）。

A．technology

B．sociology

C．physiology

D．astronomy
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单项选择题

水电机组的基本功率按相同可调容量比例分配，如果落在振动区内，应取（）。

A.相差最远的振动区边界

B.相差数值大的振动区边界

C.相差数值小的振动边界

D.相差最近的振动区边界
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