题目

请将下列物质的转化或分离方法的序号填在横线上(每一项只填写一种方法)，并指出是属于化学变化还是物理变化。①溶解 ②裂解 ③分馏 ④裂化 ⑤干馏⑥蒸馏 ⑦电解 ⑧过滤 ⑨萃取 （1） 把煤转化为焦炉气、煤焦油和焦炭等、变化。 （2） 从原油中分离出汽油、煤油、柴油等、变化。 （3） 将重油转化为汽油、变化。 （4） 将海水淡化、变化。 （5） 从海水中得到的无水MgCl2中提取金属镁、变化。As computers become all the more popular in China, Chinese people are increasingly relying on computer keyboards to input Chinese characters. But if they use the computer too much, they may end up forgetting the exact strokes（笔画）of each Chinese character when writing on paper. Experts suggest people, especially students, write by hand more. Do you write by hand more or type more? In Beijing, students start using a computer as early as primary school. And computer dependence is more wide-spread among university students. Almost all their assignments and essays are typed on a computer. All the students interviewed say they usually use a computer. It's faster and easier to correct if using a computer. And that's why computers are being applied more and more often to modern education. But when people are taking stock in computers increasingly, problems appear. "When I'm writing with a pen, I find I often can't remember how to write a character, though I feel I’m familiar with it.""I'm not in the mood to write when faced with a pen and paper."Many students don't feel this is something to worry about. Now that it's more convenient and efficient to write on a computer, why bother to handwrite? Many educators think differently. Shi Liwei , the headmaster of a famous primary school in the capital said "Chinese characters enjoy both practical and aesthetic(审美的) value. But those characters typed with computer keyboards only maintain their practical value. All the artistic beauty of the characters is lost. And handwriting contains the writer's emotion. Through one's handwriting, people can get to know one's thinking and personality. Beautiful writing will give people a better first impression of them"To encourage students to handwrite more, many primary schools in Beijing have made writing classes compulsory(必修的)and in universities, some professors are asking students to turn in their homework and essays written by hand1.Which of the following can best serve as the title of the passage?A.The Importance of Handwriting and TypingB.To Type or To Hand WriteC.Writing By Computer Will Replace Writing By HandD.Practical and Aesthetic Value of Chinese Characters2.The students interviewed prefer to write using a computer mainly because______A.they are usually asked to e-mail their Homework and EssaysB.they can correct the mistakes they make quickly and convenientlyC.they find it not easy to remember how to write a characterD.computers have become a trend and fashion in China3.Which of the following statements is NOT TRUE of the advantages of handwriting?A.Handwriting contains the writer's emotionB.The writer’s thinking and personality are shown in his or her handwriting,C.Handwriting can impress people well and build one’s self-confidenceD.Chinese characters enjoy both practical and aesthetic value