问题
填空题
碳具有可燃性,当氧气充足时生成二氧化碳,当氧气不足时生成一氧化碳。现将2.4 g碳和4.8 g氧气放在密闭容器内点燃充分反应,则密闭容器内一氧化碳的质量为 g。利用下列实验装置测定密闭容器内混合气体中一氧化碳的体积,正确连接装置的顺序是 (填接口字母)。
答案
2.8,debac
碳具有可燃性,当氧气充足时生成二氧化碳,当氧气不足时生成一氧化碳。现将2.4 g碳和4.8 g氧气放在密闭容器内点燃充分反应,则密闭容器内一氧化碳的质量为 g。利用下列实验装置测定密闭容器内混合气体中一氧化碳的体积,正确连接装置的顺序是 (填接口字母)。
2.8,debac
在方框中选择适当的句子补全对话。 | |
A: Hello, Max. How are you? B: Fine, thanks. A: 1 .You look pale (苍白 ) and tired. Is anything wrong? B: Well, yes, perhaps you can give me some advice. A: Of course, if I can. B: Well, I can't sleep at night. 2 . A: Oh, dear! That's terrible! No wonder you look so sleepy and tired. If I were you, 3 . B: Yes. Every night I go to the playground and run. But still I can't fall asleep. A: I think you can drink a cup of milk before you go to bed. 4 . B: I'll try it tonight. A: And you should relax a while and 5 Maybe you can go out for a holiday. B: That sounds nice. Thank you.
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