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问题 填空题

A、B、C、D、E、F、G七种短周期主族元素的原子序数依次增大，D、G同主族，A与B、C、D能形成电子数相同的二种常见分子，E、F的原子序数之和是D的原子序数的3倍，D、E、F的简单离子具有相同电子层结构．

（1）三种元素的名称．B______，D______，F______．

（2）A与D、A与G均可形成18e-的化合物．两种化合物在水溶液中反应的化学方程式为：______

（3）A、D、E三种元素中的两种或三种形成的物质中，含有非极性键的离子化合物的电子式为：______；只含离子键的化合物的电子式为：______．

（4）E离子的半径______（填“大于”“小于”或“等于”） F离子的半径；E 和F元素最高价氧化物对应的水化物之间反应的离子方程式为：______．

（5）写出由上述各种元素形成的粒子中与BC-电子数相等的三种分子的化学式______、______、______．

答案

由短周期主族元素的原子序数依次增大，A与B、C、D能形成电子数相同的二种常见分子，由常见的10e-和18e-微粒可知，则A为氢，B为碳、C为氮、D为氧；D、G同主族，则G为硫；E、F的原子序数之和是D的原子序数的3倍，D、E、F的简单离子具有相同电子层结构，由

8×3
2
=12可知，E为钠，F为铝，

（1）B为碳，D为氧，F为铝，故答案为：碳；氧；铝；

（2）A与D、A与G均可形成18e-的化合物为H2O2、H2S，H2O2具有氧化性，H2S具有还原性，二者发生氧化还原反应为H2O2+H2S=S↓+2H2O，

故答案为：H2O2+H2S=S↓+2H2O；

（3）A、D、E三种元素中的两种或三种形成的物质有Na2O2、Na2O、NaOH等，含有非极性键的离子化合物为Na2O2，其电子式为

，只含离子键的化合物为Na2O，其电子式为

，故答案为：

；

；

（4）E、F的简单离子具有相同电子层结构，原子序数大的离子半径小，则铝离子的半径小，E 和F元素最高价氧化物对应的水化物分别为NaOH、Al（OH）3，发生的离子反应为

Al（OH）3+OH-=AlO2-+2H2O，故答案为：大于；Al（OH）3+OH-=AlO2-+2H2O；

（5）BC-电子数为6+7+1=14，N2的电子数为7×2=14，CO的电子数为6+8=14，C2H2的电子数为6×2+1×2=14，故答案为：N2；CO；C2H2．

单项选择题

某次调查问卷中有以下两个选项：①得到2000元的确定收益；②50%的概率得到 4000元，某个人选择了②选项，则这个人属于( )。

A．风险偏好者

B．风险厌恶者

C．风险中性者

D．普通投资者
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阅读理解

第三部分: 阅读理解（共20小题，每小题2分，满分40分）

第一节：（共15小题；每小题2分，满分30分）

It seems that beauty and women are twins. You are joking? No, I’m not. Observe for yourself. Ads on fashion flood TV screens, radio programs, magazines, newspapers, and the streets. Whether they have realized or not, women are besieged by a sea of fashion. They are taught to think that without beautiful clothes they will grow old and lose their charm. So who dares to neglet dressing up at the cost of their appearance and youth?

But I do not agree with the opinion that women have to show their minds through their looks. The richness of their mind proves to be more beautiful and attractive than their looks. A woman who has experienced many troubles and may be called “aunt” or “granny” can still maintain her beauty if she has such excellent qualities as knowledge, ability, a kind heart, great courage, concern for others, etc.

In addition, old and young, beautiful and ugly are relative concepts. People who keep a young mind will never feel old. Curious about new things and eager to learn more, they keep up with the tide. Painly dressed women may have a type of beauty, which is pure and real.

Reading and learning are the best way to keep one youthful. Good books are fertile soil which can feed the flower of one’s heart and looks.

56.The underlined word “besieged” may mean _______.

A. belonged to        B. beside         C. drew          D. surrounded with

57. “So who dares to neglet dressing up at the cost of their appearance and youth?” means_______.

A. no one dares to notice that dressing up needs money

B. no one dares to fail to care for her appearance and youth with dressing up

C. everyone dares to notice that dressing up needs money

D. everyone dares to fail to care for her appearance and youth with dressing up

58. What’s the writer’s attitude of this passage?

A. He thinks that richness is beautiful.

B. It’s impossible to be old if you keep a young mind.

C. The richness of the mind is really beautiful.

D. An old lady can keep her beauty if she has knowledge.
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