问题 选择题

短周期元素Q、R、T、W在元素周期表中的位置如右图所示,其中T所处的周期序数与主族序数相等,下列推断正确的是

 QR 
T  W
 

A.T的氧化物是光导纤维的主要成分

B.W的氢化物的化学式为HCl

C.R的最高正价氧化物的水化物是弱电解质

D.Q与氢形成的化合物均含极性共价键

答案

答案:D

题目分析:图中位于第三周期第IIIA族元素T为铝,以此为突破口,可以顺利推导出Q、R、W分别为碳、氮、硫。T是铝,铝的氧化物为氧化铝,光导纤维的主要成分是二氧化硅,故A项错误;W是硫,硫的氢化物为硫化氢(H2S),故B项错误;R是氮,氮元素最高正价氧化物的水化物是硝酸(HNO3),硝酸是强酸、强电解质,故C项错误;Q是碳,碳与氢形成的化合物成为烃,烃分子中一定含有C—H键,碳、氢是不同非金属,则C—H键是极性共价键,故D项错误。

阅读理解

阅读理解。

     There are 45 students in our class. I have made a survey, 36 students say they like to exercise.

Most boys play basketball together twice a week. But girls think basketball is difficult for them,

they'd like to play volleyball together twice a week. My friend, Tony, is good at running. He runs

fastest (最快) in our class. He runs for 30 minutes on the playground every evening before he

goes to bed. Is it interesting? Gray is good at swimming. He goes to the swimming club three

times a month in winter, and three times a week in summer. So he is pretty healthy. Some of

my classmates have good eating habits. They eat both meat and vegetables. 70% of them drink

milk every day. 15 students say they drink milk three or four times a week. But some students

like to eat junk food, especially Sally. What's worse (更糟糕的) is that she doesn't like to exercise,

so she is very fat. She always says " I'm going to lose weight (减肥) tomorrow."

1. How often do most boys play basketball? [ ]

A. Every day.

B. Twice a day.

C. Twice a week.

D. Twice a month.

2. Why do the girls dislike to play basketball?  [ ]

A. Because they have no time.

B. Because they think it is not easy.

C. Because they don't like to play with the boys.

D. Because they don't like to exercise.

3. When does Tony often run for 30 minutes? [ ]

A. Every morning.

B. Every afternoon.

C. Every evening before he goes to bed.

D. Every evening before supper.

4. How often does Gray swim in winter? [ ]

A. Three times a month.

B. Three times a week.

C. It isn't mentioned in the passage.

D. Hardly ever.

5. Why is Sally so fat? [ ]

A. Because she doesn't like to exercise.

B. Because she likes to eat junk food very much.

C. Because she eats too much meat, but doesn't exercise.

D. Because she doesn't like to exercise, and she likes to eat junk food.

单项选择题