4.6g常见的有机物A在空气中完全燃烧，产生二氧化碳8.8g，产生水蒸气5.4g
有机物A的名称____________________
若有机物A不完全燃烧，只产生一氧化碳和水，请问此4.6g有机物A不完全燃烧最多能产生多少克有毒气体？
（1）乙醇（2分）（2）5.6g
题目分析：（1）根据质量守恒定律反应前后原子的种类和数量不变，知有机物中一点含有碳和氢元素，是否含有氧元素根据生成的二氧化碳中的碳元素和水中的氢元素 的质量之和与有机物的质量进行比较得出答案，故碳元素的质量为：8.8g×
=2.4g;氢元素的质量为：5.4g×
=0.6g;2.4g+0.6g=3g<4.6g；所以含有碳氢氧三种元素，原子个数比为;
:
:
=2:6:1,故化学式为C2H6O 为乙醇。根据质量守恒定律知C→ CO
28
2.4g x 12:28=2.4g:x x=5.6g
答：有机物的名称为乙醇，生成有毒气体的质量为5.6g
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| My husband has been ill in hospital for two months and I have learned to make do with very little (凑合过日子). One Sunday afternoon, I went to buy a 1 for my daughter with my friend. A woman who was also buying books in the bookstore saw me and said, "I 2 you must be having a hard time." I just smiled and said, "I'm okay. I have eight dollars and I have food at home, so I'll be 3 ." A  bout ten 4 later she came up to me and said, "Can I take a look at the book that you've 5 ? It seems very interesting!" I said all right and gave it to her. Just then 6 called me and I immediately went out. 7 I returned she thanked me and 8 my book. On my way home my friend who was driving said, "You told me you didn't had much 9 ?" I replied, "I don't." She said, "Oh yes, you do!" I assured (向……保证) her I 10 had two dollars left, but still she insisted I 11 plenty of money. "Look at your book in your bag," she 12 . "There's a hundred dollar bill in it." I turned over the page and got so 13 ! There actually was a hundred dollar 14 that seemed to have fallen out of my book! I 15 her, very surprised, and said, "I don't know 16 that came from. I have no idea because I certainly did not have a hundred 17 !" I thought and thought about the money for days after that. Then I realized it must have come from 18 who asked to borrow my book in the bookstore. How 19 of her! And what a wonderful gift to 20 when I am down to my last two dollars! | ||||
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阅读下面短文，掌握其大意，然后从21-30各题所给的A、B、C和D项中，选出最佳选项，并在答题卡上将该项涂黑。 One day, Miss Ellis gave her pupils a new kind of homework: homework on happiness. Her pupils would be “happiness 1 ”, and were to see what would happen when they tried to bring happiness to those around them. As part of their homework, all the students did really 2 , wonderful things, but what Carla Chalmers did left everyone 3 . Several days after the homework had been handed out, Carla turned up carrying a big bag. “Here in this bag I have all the happiness I’ve collected so far,” she said 4 . On seeing this, everyone was filled with 5 , but Carla didn’t want to show anyone what was in the bag. Instead, she pulled out a small box and gave it to her teacher. When Miss Ellis had taken the box, Carla took a(n) 6 camera out of her own pocket and stood with it at the ready. “Open it, Miss Ellis.” The teacher slowly opened the box and looked inside. A big smile 7 on her face, and at that moment Carla took a photo, Carla’s photo came out of the camera immediately, and she 8 it to Miss Ellis along with a sheet of paper. The teacher read the paper in silence, and when she, had finished, she gestured at the 9 . “Oh, so it’s…” “Yes!” 10 Carla, opening the bag. “It’s a great big pile of smiles!” She opened the bag and photos of different 11 fell out. The rest of the class tried to 12 how Carla had managed to create such a great big chain of happiness. All there in the box was a photo of a big smile. But everyone who had seen it felt happiness being transmitted（传送）to them, and in return, without 13 , every person 14 with a smile of their own. She managed to 15 understanding of the smile truth that every time you smile you are sending a gift to the world.
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