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问题 问答题

根据粒子的结构示意图，我能回答下列问题：

（1）表示同种元素的粒子是______（填序号）；

（2）在化学反应中容易得到电子的粒子是______（填序号）．

（3）随着“神舟六号”的发射成功，我国还将发射绕月探测卫星．其任务之一是寻找一种新能源--氦3，氦3原子核是由一个中子和两个质子构成的，其原子核外电子数为______．

答案

（1）表示同种元素的粒子是A、D；

（2）在化学反应中容易得到电子的粒子是A、C．

（3）由题意：新能源--氦3，则氦3原子核是由一个中子和两个质子构成的，根据“核内质子数=核外电子数”，可知其原子核外电子数2．

故答为：（1）A、D；（2）A、C．（3）2．

单项选择题

Anthropology is the study of human beings as creatures of society. It (1) its attention upon those. physical characteristics and industrial techniques, those conventions and values, which (2) one community from all others that belong to a different tradition.

The distinguishing mark of anthropology among the social sciences is that it includes for serious study other societies (3) our own. For its purposes any social (4) of mating and reproduction is as significant as our own. To the anthropologist our customs and those of a New Guinea tribe are two possible social schemes for (5) a common problem, and in so far as he remains an anthropologist he is (6) to avoid any weighting of one (7) the other. He is interested in human behavior, not as it is shaped by one tradition, our own, but as it has been shaped by any tradition (8) He is interested in a wide (9) of custom that is found in various cultures, and his object is to understand the way in which these cultures change and (10) , the different forms through which they express themselves and the (11) in which the customs of any peoples function in the lives of the (12) .

Now custom has not been commonly regarded as a (13) of any great moment. The inner workings of our own brains we feel to be uniquely (14) of investigation, but custom, we have a way of thinking, is behavior at its most commonplace. (15) , it is the other way round. Traditional custom is a mass of detailed behavior more astonishing than (16) any one person can ever evolve in individual actions. Yet that is a rather (17) aspect of the matter. The fact (18) first rate importance is the predominant role that custom (19) in experience and belief, and the very great varieties it may (20)

18（）

A.in

B.of

C.at

D.to
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单项选择题 A1/A2型题

在用硝酸汞滴定法测定水样中氯化物的过程中，待测溶液pH应严格控制在（）

A.3.0±0.2

B.4.0±0.2

C.5.0±0.4

D.4.0±0.4

E.3.6±0.3
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