问题 填空题

海洋为人类提供了宝贵的自然资源。

(1)食用海鱼摄取的主要营养素是          

(2)下图为海水淡化装置,利用的能源是           ,获得的蒸馏水属于        (填字母序号)。

A.单质B.化合物C.混合物

(3)从海水中提取食盐,采用的方法是        

(4)用氯化钠和碳酸氢铵()可制备碳酸氢钠和氯化铵(),该反应可表示为:。    

20℃时,按上述化学方程式中反应物的质量比,向100 g水中加入 g NaCl和 g 。理论上从溶液中析出晶体的质量为       g。

资料:20℃时四种物质的溶解度如下,假设它们同时溶解在水中各自的溶解度不变。

答案

(1)蛋白质; 

(2)太阳能;B ; 

(3)蒸发溶剂结晶;

(4)7.2g

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Iceland is a popular European tourist destination. Before you go there, it is good to learn some of the basic Iceland customs first.

Just like other countries in Europe, it is one of the customs in Iceland to shake hands and say “Hello”. Kissing each other’s cheeks is acceptable along with wishing each other a happy day.

Another custom is to take off your shoes in the hallway(走廊) when you enter someone’s home. Also, don’t be surprised if someone invites you to their house, since Icelanders love to have guests. Just make sure you take flowers or a similar token of thanks to give them.

If you have been invited to eat, keep in mind that you don’t need to express thanks before meals like the French or the Japanese. Rather, eat heartily and then thank your host afterwards by shaking his hand.

Keep in mind that believing in mysterious beings is part of the tradition in Iceland. Indeed, most of the unique and sometimes strange rock formations in Iceland are due to elves(小精灵), according to the people of Iceland.

Are you planning to spend Christmas in Iceland? If so, make sure you practice saying “Gleileg jol got tog fars!” first, which is the local Christmas greeting. It is part of the tradition in Iceland to have long Christmas holidays—26 days—longer than in any other European country. There are 13 Santa Clauses in Iceland, too!

There may not be a law requiring you to follow the customs, but there is no harm in doing so. Following them, you might be rewarded with a rich cultural experience and a more meaningful trip.

小题1: When you are invited to someone’s home in Iceland, you'd better do all of the following EXCEPT ______.

A.eating heartily and enjoying your time there

B.expressing your thanks to the host before you eat

C.taking some flowers or something else to the host

D.taking off shoes in the hallway before you enter the home小题2:Which of the following is one of the differences in customs between Iceland and France?

A.Shaking hands when greeting.

B.A 26-day-long Christmas holiday.

C.Saying hello when meeting each other.

D.Kissing each other’s cheeks when greeting.小题3:The text is mainly about ______.

A.what some of the customs in Iceland are like

B.why some of the customs in Iceland are special

C.how some of the customs in Iceland were formed

D.what some of the customs are like in Europe小题4: In the text, the author aims to tell us that ______.

A.happiness is a form of courage

B.when in Rome, do as the Romans do

C.practice is the only path to knowledge

D.everyone has good and bad times in life