试题与答案

甲和乙两种物质的溶解度曲线如图所示: (1)20℃时,甲物质的溶解度______

题型:问答题

题目:

甲和乙两种物质的溶解度曲线如图所示:

(1)20℃时,甲物质的溶解度______(填“大于”、“等于”或“小于”)乙物质的溶解度;

(2)60℃时,在100g水中加入80g甲固体,充分搅拌所得溶液的质量分数是______.

(3)80℃时,某溶液所溶解的甲和乙物质都已饱和.把该溶液冷却到室温,有晶体析出,经检验发现析出的晶体主要是甲,其原因是______(填编号)

①80℃时,甲的溶解度更大;

②80℃时,乙的溶解度更大;

③甲的溶解度受温度变化的影响比乙大.

(4)若有一甲的溶液中混有少量乙要提纯甲可采用______方法.

答案:

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参考答案:A, B, C, D

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题型:阅读理解

阅读理解。

     People travel for a lot of reasons. Some travelers go to see battlefields or religious shrines. Others are

looking for culture, or simply want to have their photos taken in front of famous places. But most Europeans

are willing to pay a lot of money and put up with a lot of inconveniences for the sun because they have so

little of it. Residents of cities like London, Copenhagen, and Amsterdam spend a lot of their winter in the

dark because the days are so short and much of the rest of the year is in the rain. Every summer, more than

25 million people travel to Mediterranean (地中海) resorts and beaches for their vacation. They all come for

the same reason: sun.

     The huge crowds mean lots of money for the economies of Mediterranean countries. Italy's 30,000 hotels

are booked every summer. And 13 million people camp out on French Beaches, parks, and roadsides. Spain's

long sandy coastline attracts more people than anywhere else. 37 million tourists visit yearly, or one tourist

for every person living in Spain.

     But there are signs that the area is getting more tourism than it can handle. The Mediterranean is already

one of the most polluted seas on earth. And with increased tourism, it's getting worse. The French can't figure

out what to do with all the garbage left by campers around St. Tropez. And in many places, swimming is

dangerous because of pollution.

     None of this, however, is damaging anyone's fun. The Mediterranean gets more popular every year with

tourists. Obviously, they don't go there for clean water. They stand traffic jams and seem to like crowded

beaches. They don't even mind the pollution. No matter how dirty the water is, the coastline still looks beautiful. And as long as the sun shines, it's still better than sitting in the cold rain in Berlin, London, or Oslo.

1. It can be inferred from the passage that Europeans travel mostly for the reason that ______.

A. they want to see battlefields or religious shrines

B. they are interested in different cultures

C. they would like to take pictures in front of famous sites

D. they wish to escape from the cold, dark and rainy days back at home

2. In Para.1, cities like London, Copenhagen, and Amsterdam are mentioned to show that ______.

A. they are not good cities in geography and climate

B. how rich their residents are

C. these cities lack places of historic interest and tourist spots

D. they have got more tourism than they can handle

3. According to the passage, which of the following countries attracts more tourists than the others?

A. Italy

B. Spain

C. France

D. Greece

4. The sentence "one tourist for every person living in Spain" (Para.2 ) means _______.

A. every year the number of tourists is equal to(等于) the number of people living in Spain

B. all the 37 millions people living in Spain are tourists

C. every person living in Spain has to take care of a tourist

D. every Spanish is visited by a tourist every year

5. Which of the following will damage the tourists' fun at Mediterranean resorts and beaches?

A. Polluted water.

B. Crowded buses.

C. Traffic jams.

D. Rainy weather

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