周期表中前四周期中的六种元素A、B、C、D、E、F原子序数依次增大,已知A原子2

题型:填空题

问题:

周期表中前四周期中的六种元素A、B、C、D、E、F原子序数依次增大,已知A原子2p轨道有3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单质的晶体熔点在同周期形成的单质中是最高的;F2核外各电子层电子均已充满。

根据以上信息回答下列问题:

(1)写出D原子核外电子排布式:____________________________________________。

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

(3)B的氯化物的熔点比D的氯化物的熔点________(填“高”或“低”);理由是_______________________________________________________。

(4)E的最高价氧化物分子的空间构型是________,是________(填“极性”或“非极性”)分子。

(5)E、F形成的某种化合物有如图所示的晶体结构:该化合物化学式为________;E原子配位数为________________________________________________。

考点:物质性质的研究
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Acting is such an over-crowded profession that the only advice that should be given to a young person thinking of going on the stage is "Don’’t!". But it is useless to try to discourage someone who feels that he must act, though the chances of his becoming famous are slim. The normal way to begin is to go to a drama school. Usually only students who show promise and talent are accepted, and the course lasts two years. Then the young actor or actress takes up work with a repertory company, usually as an assistant stage manager. This means doing everything that there is to do in the theatre: painting scenery, looking after the furniture, taking care of the costumes, and even acting in very small parts. It is very hard work indeed. The hours are long and the salary is tiny. But young actors with the stage in their blood are happy, waiting for the chances of working with a better company, or perhaps in films or television.Of course, some people have unusual chances which lead to fame and success without this long and dull training. Connie Pratt, for example, was just an ordinary girl working in a bicycle factory. A film producer happened to catch sight of her one morning waiting at a bus stop, as he drove past in his big car. He told the driver to stop, and he got out to speak to the girl. He asked her if she would like to go to the film studio to do a test, and at first she thought he was joking. Then she got angry and said she would call the police. It took the producer twenty minutes to tell Connie that he was serious. Then an appointment was made for her to go to the studio the next day. The test was successful. They gave her some necessary lessons and within a few weeks she was playing the leading part opposite one of the most famous actors of the day. Of course, she was given a more dramatic name, which is now world-famous. But chances like this happen once in a blue moon!

An assistant stage manager’’s job is difficult because he has to________.

A.do all kinds of stage work

B.work for long hours

C.wait for a better company

D.act well

题型:填空题

把一株蕨剖开,就会发现它的根、茎、叶内都有专门运输物质的管道,这就是(  )

A.导管

B.筛管

C.输导组织

D.机械组织

题型:填空题

进入青春期,男孩遗精,女孩子来月经,性意识开始萌动,都是正常的生理、心理变化。[ ]

题型:填空题

有关肝炎病毒的叙述,错误的是()

A.HAV属RNA病毒

B.HBV属DNA病毒

C.HCV属RNA病毒

D.HDV属DNA病毒

E.HEV属RNA病毒

题型:填空题

公民道德建设的原则是()。

A.为人民服务

B.讲文明、树新风

C.发展先进文化

D.集体主义

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