搜题请搜索小程序“爱下问搜题”
问题 问答题

如图所示为实验室常用的实验装置．据图，回答下列问题．

（1）写出带有标号的仪器名称：①______；②______．

（2）常温下，可用过氧化氢溶液和二氧化锰固体混合制取氧气，可以选用的气体发生和收集装置组合有______．

（3）实验室通常选用上图中的B装置制二氧化碳，该反应的化学方程式为______．F装置可用来测量生成的CO2气体体积，其中在水面上放一层植物油的目的是______．植物油上方原有的空气对实验结果______（填“有”或“没有”）明显影响．

答案

AB应属于发生装置，其余的是收集装置．装置A适于固体加热的反应，而装置B适于固液不需要加热的反应．c适于密度小于空气的气体收集装置，D适于密度大于空气的气体收集；E适合收集不易溶于水的气体．

（1）①②是实验室制取气体时常用的仪器长颈漏斗和集气瓶；

（2）实验室通常用双氧水制氧气时，常用MnO2作催化剂；属于固液常温型装置，选B，氧气密度大于空气，不易溶于水，收集方法可选D或E；

（3）实验室制取二氧化碳常用石灰石和稀盐酸反应，而F中的植物油就起到避免二氧化碳和水反应的可能．影响实验的准确性．

故答案为：

（1）①长颈漏斗；②集气瓶．

（2）B、D或B、E．

（3）CaCO3+2HCl=CaCl2+H2O+CO2↑；

防止二氧化碳溶于水或与水反应；没有．

完形填空
完型填空（15分）
I have had thousands of classes since I started school nine years ago. But only one _1_ was the most important.
It happened last term just after I had got a _2_ result in an exam. I was sad and had lost my confidence. I decided to go to a class which can tell me how to be_3_.
The speaker walked into the room. But he did not start talking _4_ a teacher. Instead, he held up a twenty Yuan note(钞票)!
“Who wants this?” he asked. Unsurprisingly, _5_ of us in the class held up our hands.
The speaker smiled. Then he put up the note on the blackboard and asked the same question. Again, we all put up our hands. The speaker smiled again, but _6_nothing. Suddenly, he threw the note onto the floor! Then he asked the same _7_ a third time.
I didn’t _8_ what the speaker was doing. Why was he asking the same question again and again? I didn’t know what to do. I wanted the note, _9_ I put my hand up again. After a while, he _10_ the note and started to laugh. “You have all just told me how to become successful,” _11_ said to us with the note in his hand.
“The note is worth twenty yuan. It is _12_ worth twenty yuan, even though I throw it on the floor. You are like the note. No matter _13_ happens to you, you still have your worth.”
When I heard those words, I was deeply moved. Suddenly, I _14_ I was worth a lot. I may have done badly in an exam, but it doesn’t _15_ I can’t do well in the future. If I believe in myself, I will be successful!
小题1:
A．classroomB．subjectC．classD．school
小题2:
A．sameB．goodC．luckyD．bad
小题3:
A．comfortableB．successfulC．famousD．rich
小题4:
A．likeB．forC．aboutD．by
小题5:
A．bothB．neitherC．allD．none
小题6:
A．saidB．boughtC．sawD．wanted
小题7:
A．studentB．teacherC．questionD．way
小题8:
A．rememberB．understandC．noticeD．find
小题9:
A．soB．thoughC．ifD．or
小题10:
A．took outB．threw awayC．picked upD．put down
小题11:
A．youB．heC．sheD．they
小题12:
A．neverB．sometimesC．hardlyD．always
小题13:
A．whenB．whoC．whatD．how
小题14:
A．realizedB．forgotC．dreamedD．decided
小题15:
A．knowB．meanC．thinkD．complain
查看答案
实验题

（10分）某研究性学习小组利用如图所示装置完成有关实验。

【实验一】快速制氨气

（1）用装置I快速制氨气，则装置I的a仪器中可加入浓氨水，b仪器中加入          。装置Ⅱ从      管口进气可作为氨气的收集装置。

【实验二】收集NO

（2）利用装置Ⅱ可收集NO,试简述操作方法：                                      。

【实验三】比较硫、碳、硅三种元素的非金属性强弱

（3）设计实验，完成下列表格（可以不填满，也可以再加行）

装置序号仪器中所加物质名称现象
   
   
   
查看答案