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问题 问答题

请根据下面提供的装置图回答问题：

（1）仪器甲的名称是____________。

（2）实验室制二氧化碳的化学方程式为         。

（3）用过氧化氢溶液和二氧化锰制氧气的化学方程式为       ，发生装置若选用C你认为装置C的主要优点是     。能用于收集氧气的是        ，原因是     。

答案

（1）试管

（2）CaCO3+2HCl =" CaCl" 2+CO2↑+H2O ；

（3）2H2O22H2O + O2↑；可以控制过氧化氢的用量，节约药品。D或E；相同条件下，氧气密度比空气大，且不易溶于水。

分析：（1）熟悉常见仪器，了解名称；

（2）熟记实验室制取二氧化碳的反应式；

（3）熟记实验室制取氧气的化学反应式；C装置中的注射器可以随时控制过氧化氢的用量；根据氧气密度大于空气密度和不易溶于水的特点选择收集方法．

解答：解：（1）图中甲是试管．

故答案为：试管．

（2）实验室常用大理石和稀盐酸反应制取二氧化碳，化学反应式是：CaCO3+2HCl=CaCl2+CO2↑+H2O；

故答案为：CaCO3+2HCl=CaCl2+CO2↑+H2O．

（3）用过氧化氢溶液和二氧化锰制氧气的化学方程式为：2H2O22H2O+O2↑；装置C添加液体用注射器，它可以随时控制反应的发生和停止，节约药品；因氧气的密度大于空气的密度，并且不易溶于水，所以可用排水法和向上排空气法收集氧气．

故答案为：2H2O2

2H2O+O2↑；可以控制过氧化氢的用量，节约药品；D或E；相同条件下，氧气密度比空气大，且不易溶于水．

单项选择题

新生儿窒息抢救措施中，不正确的是

A．首先用酒精檫胸，刺激呼吸

B．吸尽黏液及羊水后，拍打新生儿脚掌促使啼哭

C．窒息严重的患儿，可用咽喉镜气管插管吸出黏液

D．在呼吸道通畅的基础上行人工呼吸，同时吸氧

E．重度窒息新生儿需给5%碳酸氢钠纠正酸中毒
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阅读理解

阅读下面短文, 请根据短文后的要求进行答题。（请注意问题后的字数要求）

[1]Everybody is familiar with Christmas music； its played everywhere. Whether it's the music from a grocery store or random(随机的）songs on the radio， holiday music remains to flood in the air from the day after Thanksgiving to the beginning of December. Christmas music gets extremely over- played through the Holiday season. “'I think the common seasonal Christmas music is annoying because it keeps being played over and over.”said junior Devin McFarland.

[2]The Christmas music still played today is what she heard in her childhood. Some famous Christmas songs have never been changed. The original music is played so much that in some cases people dream about or even sing Christmas music__________. She wishes that there was a wider variety of songs. She likes the newer Christmas songs that bands either re- make or write themselves. "They have a fresher sound to Christmas songs, and they add their own characteristics to them so that they are more like their own songs. ” McFarland explained.

[3]Christmas is known as a happy and homecoming festival, so the holiday season is meant to be spent happily with your family. It is recognized that the music media wants to get the point across and add to the festival atmosphere. But isn't the music being pushed to the public too much?

[4]Most grocery stores play the music non-stop ，Christmas song after Christmas song， disgusting the customers who don't like that kind of music. You can walk through stores and attempt turning off the music, but sometimes it's impossible to do so. On the other hand, almost everyone has witnessed random persons walking along happily and either singing or whistling to the tune of the song that's played throughout the store.

小题1:What is the main idea of the passage? (no more than 10 words)

小题2:Why is the common seasonal Christmas music annoying? (no more than 8 words)

小题3:What does the music media hope to tell the public?

小题4:Fill in the blank in Paragraph 2 with proper words.(no more than 3 words)

小题5:What does the word “them” (Line 6 Paragraph 2) probably refer to? (no more than 4 words)
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