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问题 填空题

天然水受到污染后，净化时需要运用科学的方法．常用的净水方法有______（写出一种即可）．漂白粉可用水的杀菌消毒，其有效成分是次氯酸钙[化学式为Ca（ClO）2]．次氯酸钙可发生如下反应：Ca（ClO）2+X+H2O=CaCO3↓+2HClO，则X的化学式为______．次氯酸钙中氯元素的化合价是______．

答案

常用的净水方法有：通过蒸馏可以达到纯净的水，从而达到净化水的目的；

通过加入化学试剂可以净化水，例如向酸性污水中加入熟石灰可以达到净化水的目的．

故填：蒸馏．

由Ca（ClO）2+X+H2O=CaCO3↓+2HClO可知，每个X中含有1个碳原子和2个氧原子，X是二氧化碳，化学式是CO2．

故填：CO2．

设次氯酸钙中氯元素的化合价为Y，

则有：（+2）×1+Y×2+（-2）×2=0，

Y=+1，

故填：+1．

单项选择题

《机械设备安装工程施工及验收通用规范》强制性条文规定：交给施工人员进行安装的机械设备，必须符合(　　 )标准的规定，并应有合格证明。

A．制造和工艺

B．设计和工艺

C．设计和产品

D．制造和产品
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问答题

A couple of years ago a group of management scholars from Yale and the University of Pittsburgh tried to discover if there was a link between a company’s success and the personality of its boss. (46)To work out what that personality was, they asked senior managers to score their bosses for such traits as an ability to communicate an exciting vision of the future or to stand as a good model for others to follow. When the data were analyzed, the researchers found no evidence of a connection between how well a firm was doing and what its boss was like. As far as they could tell, a company could not be judged by its chief executive any better than a book could be judged by its cover.
(47)A few years before this, however, a team of psychologists from Tufts University, led by Nalini Ambady, discovered that when people watched two-second-long film-clips of professors lecturing, they were pretty good at determining how able a teacher each professor actually was.
Now, Dr Ambady and her colleague, Nicholas Rule, have taken things a step further. (48)They have shown that even a still photograph can convey a lot of information about competence—and that it can do so in a way which suggests the assessments of all those senior managers were nonsense.
Dr Ambady and Mr. Rule showed 100 undergraduates the faces of the chief executives of the top 25 and the bottom 25 companies in the Fortune 1,000 list. Half the students were asked how good they thought the person they were looking at would be at leading a company and half were asked to rate five personality traits on the basis of the photograph. (49) These traits were competence, dominance, likability, facial maturity (in other words, did the individual have an adult-looking face or a baby-face) and trustworthiness.
And Dr Ambady and Mr. Rule were surprised by just how accurate the students’ observations were. The results of their study, which are about to be published in Psychological Science, show that both the students’ assessments of the leadership potential of the bosses and their ratings for the traits of competence, dominance and facial maturity were significantly related to a company’s profits.
(50)Sadly, the characteristics of likability and trustworthiness appear to have no link to company profits, suggesting that when it comes to business success, being warm and fuzzy does not matter much (though these traits are not harmful).
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