One Monday morning, Paul and his classmates were in science laboratory for their practical chemistry lesson. The students were going to work in pairs to do an experiment. Before they began, the teacher gave them this description of the different stages of the experiment.

Stage 1: Prepare the equipment: a test tube, a crucible, a Bunsen burner and tongs.

Stage 2: Weigh 5 grams of baking soda (sodium bicarbonate) and put it in a crucible.

Stage 3: Heat 10 ml of hydrochloric acid (盐酸) in a test tube.

Stage 4: Pour the warm acid onto the baking soda and continue to heat the mixture.

Result: The acid reacts with the bicarbonate(碳酸氢盐)to form water, carbon dioxide gas and salt. The hotter the mixture, the quicker the reaction. Continue to heat the mixture until the water evaporates, leaving the salt in the crucible.

Paul and his partner followed the instructions and set up their equipment. Paul went to the cupboard to get a bottle of hydrochloric acid. He found that there was only one bottle in the cupboard so he took that. There was no label on the bottle and Paul didn’t check with the teacher if it was the right solution.

He measured the liquid and poured it into a test tube. Using tongs to hold the test tube, he heated it over the Bunsen burner. That’s when things started to go wrong. The liquid in the test tube was not hydrochloric acid. When it was heated, it formed a thick cloud of white gas. Soon the room was full of this strong smelling white gas.

All the students started coughing and their eyes hurt. The teacher immediately opened the windows and ordered the students to leave the laboratory at once. She realized that the liquid was a crylamide (丙烯酰胺) and that it is poisonous.

Fortunately, nobody was injured in the incident. However, it taught the students and the teacher a good lesson.

1.What lesson did the incident teach the students and the teacher?

A. Never have a bottle without a label in the chemistry lab!

B. Obey your teacher’s instructions in the Chemistry lab.

C. A crylamide can’t take the place of hydrochloric acid.

D. Finding something unusual happened, you have to leave the laboratory at once.

2.What substance were the students making in the experiment?

A. Water              B. Carbon dioxide gas         C. Salt          D. Poisonous gas

3.Why did Paul make the mistake?

A. He went to the cupboard to get the bottle by himself.

B. He found that there was only one bottle in the cupboard so he took that.

C. There was no label on the bottle.

D. Paul didn’t check with the teacher that it was the right solution.

4.Why did the teacher send the students out of the classroom?

A. Because the room was full of this strong smelling white gas.

B. Because all the students started coughing and their eyes hurt.

C. Because the liquid was a crylamide and that it is poisonous.

D. Because someone was injured in the incident.

 

A quarter of US adults say they read no books at all in the past year, according to an Associated Press-Ipsos survey. The typical person said that he / she read four books in the last year and, excluding those who had not read any books at all, the usual number of books read was seven.

Of those who did read, women and pensioners (领养老金者) were the most eager readers, and religious works and popular fiction were the top choices. The number of books read was nine books for women and five for men. The number also showed that those with college degrees read the most, and people aged 50 and over read more than those who are younger.

People from the West and Midwest are more likely to have read at least one book in the past year. Southerners who do read tend to read more books — mostly religious books and romance novels — than people from other regions.

Those who said they never attend religious services read nearly twice as many books as those who attend frequently, but the Bible and religious works were read by two thirds of the people in the survey, more than all the other categories. Popular fiction, histories, biographies and mysteries took up about half, while one in five read romance novels. Politics, poetry and classical literature were named by fewer than 5% of readers. More women than men read every major category of books except for history and biography books. Men tend to prefer non-fiction.

Book sales in the US have been flat in recent years and are expected to stay that way, which, experts think, results from competition from the Internet and other media, and the unsteady economy.

1.The passage mainly tells us ______.

A. the number of Americans who read books last year dropped

B. the book sales in the US have been dropping in recent years

C. the reasons why one in four Americans read no books last year

D. about region differences in the number and kind of books read last year

2.Which kind of Americans read the most last year according to the survey?

A. Older men with college degrees from the South.

B. Older women with college degrees from the South.

C. Younger educated men from the Midwest.

D. Younger educated women from the West.

3.What kind of books was read most according to the passage?

A. Religious works.                        B. Popular fiction.

C. Poetry.                                        D. History.

4.Which of the following reasons why people read fewer books is true?

. Competition from the Internet.  

. Competition from other media.

. The unsteady economy.

. People attend religious services

. No time for reading.

A. ①②③                   B. ②③⑤           C. ①③⑤             D. ②③④

 

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