问题 填空题

A、B、C、D四种元素均为短周期元素,其原子半径依次减小,它们的气态氢化物分子所含的电子数相同,C元素原子的K层电子数与M层电子数之和等于L层电子数.根据以上信息,按要求写出以下化学式(用A、B、C、D所代表的真实元素符号表示).

(1)A的最高价氧化物______;

(2)B的气态氢化物______;

(3)C的最高价氧化物的水化物______; 

(4)D的单质______.

答案

A、B、C、D四种元素均为短周期元素,C元素原子的K层电子数与M层电子数之和等于L层电子数,则M层电子数为8-2=6,所以C为硫元素,氢化物为H2S;A、B、C、D四种元素,其原子半径依次减小,所以D为氯元素,氢化物为

HCl;所以A、B、C、D四种元素气态氢化物有18个电子,故A为硅元素,B为磷元素.

(1)A为硅元素,A的最高价氧化物为SiO2;         

故答案为:SiO2

(2)B为磷元素,B的气态氢化物为PH3

故答案为:PH3

(3)C为硫元素,C的最高价氧化物的水化物为H2SO4; 

故答案为:H2SO4

(4)D为氯元素,D的单质为Cl2

故答案为:Cl2

阅读理解

I will never forget the lesson about my window. Four years ago, I moved to a house in a large town. One of my new neighbors’ house was only a few feet away from mine. There lived a woman. Through one of my windows, I could see her reading by her window every afternoon.

Several months later, I found I couldn’t see the woman clearly. I thought her window was too dirty. I said to myself, “Why doesn’t she clean her window? It looks terrible!”

One afternoon, I decided to clean my house including(包括) the window. I felt tired after three hours of hard work. So I sat down by the window for a rest. What a surprise! I could see the woman reading there clearly again! By that time, I realized that my own window was too dirty, not hers! I really felt ashamed for myself. I had been watching her through my dirty window in the past days!

The experience is very important for me. So I try to clean the window of my heart before judging(评判) others.

小题1:How long has the writer lived in the house according to the passage?

A. Two years.                B. Three years.          C. Four years.    

小题2:The writer couldn’t see the woman clearly because ______________.

A. the writer’s window was dirty              

B. the woman’s house was too far

C. the woman didn’t open her window

小题3:The underlined word “ashamed” means _________________.

A. 高兴的                    B. 放松的                C. 羞愧的

小题4:According to the passage, the writer has learnt how to __________________.

A. clean the house           B. judge others          C. help neighbors

问答题 简答题