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问题 推断题

已知：A、B、C、D、E、F五种元素核电荷数依次增大，属周期表中前四周期的元素。其中A原子核外有三个未成对电子；化合物B2E的晶体为离子晶体，E原子核外的M层中只有两对成对电子；C元素是地壳中含量最高的金属元素；D单质的熔点在同周期元素形成的单质中是最高的；F原子核外最外层电子数与B相同，其余各层均充满。请根据以上信息，回答下列问题：

⑴A、B、C、D的第一电离能由小到大的顺序为___________。（用元素符号表示）

⑵B的氯化物的熔点比D的氯化物的熔点__________（填高或低），理由是___________。

⑶E的最高价氧化物分子的空间构型是___________。

⑷F的核外电子排布式是___________，F的高价离子与A的简单氢化物形成的配离子的化学式为___________。

⑸A、F形成某种化合物的晶胞结构如图所示，则其化学式为__________；（黑 * * 表示F原子） 

⑹A、C形成的化合物具有高沸点和高硬度，是一种新型无机非金属材料，其晶体中所含的化学键类型为_____________。

答案

⑴Na＜Al＜Si＜N

⑵高;NaCl为离子晶体而SiCl4为分子晶体

⑶平面正三角形

⑷1s22s22p63s23p63d104s1（或[Ar] 3d104s1）； [Cu(NH3)4]2+ 

⑸Cu3N  

⑹共价键

判断题

骨关节炎不应在关节内注射皮质激素类药物。()
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单项选择题

The idea of test-tube babies may make you either delighted at the wonders of modern medicine or irritated while considering the moral, or legal, or technological implications of starting life in a laboratory. But if you’’ve ever been pregnant yourself, one thing is certain: You wonder what it’’s like to carry a test-tube baby. Are these pregnancies normal Are the babies normal The earliest answers come from Australia, where a group of medical experts at the Queen Victoria Medical Center in Melbourne have taken a look at the continent’’s first nine successful invitro pregnancies. The Australians report that the pregnancies themselves seemed to have proceeded according to plan, but at birth some unusual trends did show up. Seven of the nine babies turned out to be girls. Six of the nine were delivered by Caesarean section. And one baby, a twin, was born with a serious heart defect and a few days later developed life-threatening problems.What does it all mean Even the doctors don’’t know for sure, because the numbers are so small. The proportion of girls to boys is high, but until there are many more test-tube babies no one will know whether that’’s something that just happened to be like that or something special that happens when egg meets sperm in a test tube instead of a fallopian tube. The same thing is true of the single heart defect. It usually shows up in only 15 out of 60,000 births in that part of Australia, but the fact that it occurred in one out of nine test-tube babies does not necessarily mean that they are at special risk. One thing the doctors can explain is the high number of Caesareans. Most of the mothers were older, had long histories of fertility problems and in some cases had had surgery on the fallopian tubes, all of which made them likely candidates for Caesareans anyway.The Australian researchers report that they are quite encouraged. All the babies are now making normal progress, even the twin with the birth defects.

What is the author’s tone in this passage

A．Depressed.

B．Optimistic.

C．Opposing.

D．Negative.
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