问题 填空题

(10分)下表是元素周期表中的一部分,根据A~I在元素周期表中的位置,用元素符号或化学式回答下列问题:

   族

周期

ⅠAⅡAⅢAⅣAⅤAⅥAⅦA0
1A       
2   DE GI
3B C F H 
(1)上表中,化学性质最不活泼的元素是_____,氧化性最强的单质是_____,还原性最强的是_____。

(2)最高价氧化物对应水化物的碱性最强的元素是________,酸性最强的元素是________。

(3)A分别与D、E、F、G、H形成的化合物中,最稳定的是___________。

(4)请用电子式表示化合物BG的形成过程_________________________________。

(5)写出C的最高价氧化物对应水化物与B的最高价氧化物对应水化物反应的离子方程式:_______________________________________________________。

答案

(1)He,F2,Na         (2)Na,Cl。

(3) HF。      (4)

(5) Al(OH)3 + OH-=AlO2- + 2H2O

考查元素周期表的结构及元素周期律的应用。根据元素在周期表中的位置可知A~I分别是H、Na、Al、C、N、P、F、Cl、Ar。同周期自左向右金属性逐渐减弱,非金属性逐渐增强;同主族自上而下非金属性逐渐减弱,金属性逐渐增强。金属性越强最高价氧化物的水化物的碱性越强,非金属性越强,最高价氧化物的水化物的酸性越强,相应氢化物的稳定性越强。

单项选择题

There are many kinds of friends. Some are always (1) you, but don’t understand you. Some say only a few words to you, but understand you. Many people will step in your life, but only (2) friends leave footprints.

I shall always recall the autumn and the girl with the (3) . She will always bring back the friendship between us. I know she will always be my best friend.

It was the golden season. I could see the yellow leaves (4) with the cool (5) . In such a season, I liked walking alone on the roads covered with leaves, (6) to the sound of them.

Autumn is a (7) season and life is uninteresting. The free clays always get me (8) . But one day, the sound of a violin (9) into my ears like a stream flowing in them ountains. I was so surprised that I jumped to see what it was. A young girl, standing in the wind, was (10) in playing her violin.

I had (11) seen her before. The music was so nice that I listened quietly. Lost in the music, I didn’t know that I had been (12) there for so long but my existence did not seem to disturb her.

Leaves were still falling. Every day she played the violin at the comer of the building (13) I went downstairs to watch her performance. I was the only listener. The autumn seemed no longer lonely and life became (14) . (15) we didn’t know each other, I thought we were already good friends. I believe she also loved me.

Autumn was nearly over. One day, when I was listening carefully, the sound suddenly (16) . To my astonishment, the girl came over to me.

"You must like music from the violin. " she said.

"Yes. And you play very well. Why did you stop" I asked.

Suddenly, a (17) expression appeared on her face and I could feel something unusual.

"I came here to see my grandmother, but now I must leave. I once played very badly. It was your listening every day that (18) me." she said.

"In fact, it was your playing (19) gave me a meaningful autumn," I answered, "Let’s be friends. "

The girl smiled, and so did I. I never heard her play again in my life. I no longer went downstairs to listen to her. Only thick leaves were left behind. But I will always remember the fine figure of the girl. She is like a (20) —so short, so bright, like a shooting star giving off so much light that makes the autumn beautiful.

20().

A.song

B.dream

C.fire

D.sister

多项选择题