问题 选择题

2010年春季,我们西南5省面临世纪大旱,5000多万同胞受灾.这场少见的世纪大旱使农作物受灾面积近500万公顷,其中40万公顷良田颗粒无收,2000万同胞面临无水可饮的绝境.下列有关水的知识,其中不正确的是(  )

A.水是一种最常见的溶剂,自然界中的水大多数含有杂质离子

B.用煮沸或蒸馏的方法能降低水的硬度

C.地球上的淡水资源很丰富,但分布不均匀

D.在水溶液中发生化学反应,反应速度比较快而且充分

答案

A、自然界中的水都不是纯净水,里面含有一些可溶性杂质,故水是一种最常见的溶剂,故A正确;

B、水中含有的可溶性钙镁化合物受热能分解为不溶性固体,从而减少水中可溶性钙镁化合物的量,可以降低水的硬度,故B正确;

C、地球上的淡水资源很不丰富,甚至缺乏,故C错误;

D、在水溶液中发生化学反应,能增加离子的接触几率,所以反应速度比较快而且充分,故D正确,

故选C.

阅读理解

阅读理解。

     Imagine yourself on a boat looking out at the horizon and all you can see is the water meeting the sky

with no land in sight and you are sailing straight ahead to meet the world. Jesse Martin does not have to

imagine: he is living in it.

     On Dec. 7, 1998, at 17 years old, Jesse set sail from Melbourne, Australia on his boat, attempting to

become the youngest person to sail alone and nonstop around the world. He sailed south of New Zealand,

through the South Pacific, around South America, north on the Atlantic, back south past Africa, through

the Indian Ocean and back to Melbourne.

     Even as a young child, Jesse had been an adventurer who traveled all over Europe and Asia with his

parents. Born in Munich, Germany in 1981, he moved to Australia with his family when he was only two

years old. They moved close to a rainforest in Cow Bay, about 3500kms north of Melbourne, where they

built a small house with no electricity or running water. Jesse grew up at the beach enjoying the outdoors

to its fullest.

     At 14, he sailed for the first time with his father and brother, Beau. It was after this trip that he began

to dream about sailing around the world.

     Jesse's family played an important role. "I was made to believe I could do anything." he says. Although,

he says, there were others that were not so encouraging or supportive, "People that I looked up to, respected

and trusted told me I couldn't. Thankfully, I trusted myself. There were people that said that the boat

couldn't be ready by the time I had to leave." However, through perseverance and belief in himself he was

able to do what many told him was impossible.

     On Oct.31, 1999, more than 10 months after he set sail, Jesse Martin went down in history as the

youngest person to sail around the world alone, nonstop and unassisted.

1. What's the author's purpose in encouraging the reader to imagine a sailing experience?

A. To show how difficult it is to be a sailor.

B. To show how wonderful Jesse's sailing is.

C. To describe what Jesse's sailing is like.

D. To describe what a sailor's life is like.

2. Jesse Martin was at the end of his voyage when he ______.

A. sailed on the South Pacific.

B. sailed on the Indian Ocean.

C. sailed past Africa.

D. sailed past South America.

3. Which of the following made Jesse decide to sail alone around the world?

A. His childhood adventure experiences.

B. His journeys to Europe.

C. His first sailing trip with his family.

D. His love for outdoor activities.

4. What can we learn from Jesse Martin's story?

A. Interest leads to success.

B. A strong belief will make a person stronger.

C. Life is an unusual adventure we should enjoy.

D. Failure is the mother of success.

单项选择题