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问题 选择题

如图为一原电池装置，下列叙述中正确的是（　　）

A．铜离子在铜片表面被还原

B．盐桥中的K+移向ZnSO4溶液

C．电流从锌片经导线流向铜片

D．铜是阳极，铜片上有气泡产生

答案

A．该原电池中，铜是正极，电极反应为Cu2++2e-=Cu，铜离子在铜片表面被还原生成铜单质，故A正确；

B．在溶液中，阳离子往正极移动，即K+移向CuSO4溶液，故B错误；

C．外电路中，电流从正极铜沿导线流向锌，故C错误；

D．该原电池中，铜片为正极，发生电极反应式为：Cu2++2e-=Cu，在铜片表面析出铜单质，没有氢气生成，故D错误；

故选A．

填空题

工业上通常以铝土矿（主要成分为Al2O3）为原料制备无水氯化铝：2Al2O3+6Cl24AlCl3+3O2 ↑。请回答下列问题：

（1）上述反应涉及的元素中，最外层有2个未成对电子的元素是__________；简单离子的离子半径最小的元素，其原子核外有_____种不同能级的电子。

（2）已知元素周期表中，镓(31Ga)与铝元素同一主族，写出Ga的最外层电子排布式：______

（3）镓(Ga)有两种天然同位素，一种是，其原子在天然同位素原子中所占的百分比为60%。实验测得溴化镓(GaBr3)的摩尔质量为309.8 g/mol，则由此推知镓的另一种同位素是_________。

（4）为促进反应的进行，实际生产中需加入焦炭，其原因是              。
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It is clear that we are rapidly becoming a global culture. New forms of information technology, intercontinental travel, and the complex nature of economics are all elements in such a change. Japan, an ancient (1) culture, now dominates the West economically while its own traditional (2) is rapidly becoming (3) in the process.
It does not take a great deal of analysis to see the vast interchanges of cultural influences in the world today. The thirst for (4) fashions, popular music, and the other elements of consumer culture (5) great inroads in non-Western lands while the West seeks out everything from the religious traditions of the Ease (6) the art and music these countries produce. In the field of (7) , to cite one conspicuous example, contemporary readers seek books (8) those of the West. Latin American authors, as well as those from Africa, Asia, and India, now find appreciative audiences.
A (9) culture does not mean a unitary or "one world" culture. It does mean that people are increasingly aware of the diversity of culture. World events enter our living rooms so that things that may once have been (10) of as distant (11) now greet us immediately and in color. We may watch those events on a television made in Japan while wearing clothes sewn in Thailand and shoes made in Hungary while snacking (12) food grown in Mexico. Such an economic interdependence reflects the reality of a global banking system, the globalization of the economy, and the increasing (13) of information and information technologies.
(14) has this shrinking of distances (and attitudes) become more clear than in the academic debates over what constitutes a liberal (15) education today. Is it possible (or desirable) to have the Western core of humanities (16) the center-piece of a curriculum The place of non-Western and non-traditional cultures as part of the general (17) of a student is hotly argued in educational circles. The very fact of that discussion (18) to the emergence of a global consciousness with a continued shrinking of parochial attitudes. The (19) that such globalization is hotly debated only emphasizes the profound nature of the (20) taking place in our culture.
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