问题 选择题

下列说法正确的是 (    )

A.从海水中提取物质都必须通过化学反应才能实现

B.二氧化硫可用于消毒杀菌和漂白纸张草帽等

C.过氧化钠、烧碱、纯碱分别属于碱性氧化物、碱、盐

D.Na、Al、Cu可以分别用热还原法、热分解法和电解冶炼法得到

答案

答案:B

题目分析:从海水中提取蒸馏水和盐时,通过蒸馏、蒸发等物理变化就能实现,提取溴、碘、镁等物质时,必须通过化学反应才能实现,A项错误;二氧化硫具有还原性,能够使一些物质褪色,因而具有漂白性且可用于消毒杀菌,B项正确;过氧化钠属于过氧化物,C项不正确;金属冶炼方法常用的有三种:①热分解法,适用于制取不活泼金属如Ag等;②热还原法,适用于制取金属活动性顺序表中Al以后、Hg以前的金属;③电解法,适用于制取金属活动性顺序表中Al及以前的还原性很强的金属,D项错误。

阅读理解

阅读理解。

     Basketball is a young game though it is over a hundred years old.  In the year of 1891, a certain

college was having some trouble with its boy students. The weather was bad. They had to stay indoors.

As they could not take part in their usual outdoor sports, they were unhappy, and some of them even

got into fights from time to time.  Finally, one of the teachers at the college asked Dr. Naismith to invent

a game so that the students might have something to play. It was not easy to invent a game because it had

to be played indoors, and the court was not very large.  Dr. Naismith thought for a few days and invented a kind of ball game. It was a fast, exciting game with much moving and passing of the ball. Usually two teams played the game.,  In order to make a score, the ball had to be thrown into a basket ten feet above the floor on the wall. At each end of the court there was such a basket. At first, Dr. Naismith had planned to

have the ball thrown into a box. As he could not find boxes of the right size, he had to use fruit baskets.

Dr. Naismith put two fruit baskets on the walls of both sides. There were nine plavers on each side. The

players tried to throw the ball into the baskets.  There were no holes at the bottom of the baskets.  When

a ball went into the basket, it stayed there.  The game had to stop.  A player had to climb up to get the

ball out. Later people used net baskets. Now only ten members play the game. There are five players on

each side. Basketball today is played in many countries.

1. The article tells us ______.      

A. what basketball is

B. how basketball was invented

C. why people like basketball

D. who played basketball

2. The underlined word "indoors" means "______"    

A. in the door                          

B. inside the room

C. in many doors                      

D. inside the doors

3. When a student threw a ball into the basket ______            

A. he made a score

B. the basket itself will be no use

C. he lost the game

D. he made a hole at the bottom of the basket

4. The game got its name from ______.           

A. the ball itself                      

B. the basket itself

C. both the basket and the ball            

D. the inventor

5.Which of the following is NOT false according to the passage?           

A. Nine players on each side play the basketball in a match today.

B. Ten players on each side play the basketball in a match today.

C. Five players on each side play the basketball in a match today.

D. Eighteen players on each side play the basketball in a match today.

单项选择题