（5分）A～G是初中常见的7种物质，它们有如下图所示的转化关系。
已知A、C是无色液体，B、F、G是无色气体，其中大量排放F会引起温室效应，D是黑色固体，E在纯净的B中燃烧发出明亮的蓝紫色火焰。
（1）请写出下列物质的化学符号：D___________，G___________，H___________。
（2）请写出下列变化的文字表达式：①B→F___________，②C→B___________。
（1）C SO2 H2
（2）①碳+氧气
二氧化碳 ②水
氢气+氧气
解答推断题应从最明显的现象和最容易的物质入手。本体最好推断的物质是F，能引起温室效应肯定是CO2，因此黑色固体D是C，B物质是O。在二氧化锰作用下分解出氧气的物质很明显A是H2O2，生成的C是H2O。水通电生成氧气和氢气，因此H是H2。又由于E在氧气中燃烧发出明亮的蓝紫色火焰所以E是S，生成的G是SO2。
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| It's Sunday. We are in the park now. __1__ is a big and beautiful park. __2__ many people in it. We all like this park. The park__3__ a lake. too.We can boat on the 1ake. But we__4__ swim in it. It is dangerous. Look at that family. They are__5__ the tree. The boy is on the left of his father. The family bring their__6__ to the park. It is a cat,a white cat. How lovely! The boy has a __7__ in his hand. He wants to fly it. But I think they__8__ look for the right place. It's not a good place here. There are too many trees. The mother has a beautiful handbag. It's __9__ . I like the colour. It's the color of the sky (天空). There is a __10__ on the tree. It says" Don't climb (爬) the tree!" But the cat is in the tree now. | |||
| ( ) 1. A. He ( ) 2. A. There are ( ) 3. A. have ( ) 4. A. can ( ) 5. A. on ( ) 6. A. son ( ) 7. A. ball ( ) 8. A. are ( ) 9. A. yellow ( ) 10. A. sign | B. It B. There is B. haves B. can't B. in B. pet B. plane B. must B. black B. newspaper | C. They C. There have C. is C. must C. under C. teacher C. shirt C. do C. white C. book | D. There D. There has D. has D. must't D. into D. cat D. kite D. can D. blue D. bag |