(1)实验室制取气体是初中非常重要的一组实验,结合下列实验装置图回答有关问题:

题型:问答题

问题:

(1)实验室制取气体是初中非常重要的一组实验,结合下列实验装置图回答有关问题:

①仪器a的名称是______.小强想用氯酸钾与二氧化锰加热制氧气,应选用的气体发生装置是______(填字母),发生反应的文字表达式是______.小红想用过氧化氢溶液和二氧化锰来制取氧气,应选择的气体发生装置是______(填装置序号),在加试剂之前的操作是______;发生反应的文字表达式是______.请你比较小红与小强的方法,其中小红选择的方法的优点有______(答一条).

②小刘同学善于动脑筋,在复习“铁在氧气里燃烧”实验后,他进行了一系列思考和探究:实验时在集气瓶里加少量水,其目的是______,发生反应的文字表达式是______.该反应属于______反应(填反应类型”);在复习“硫粉在氧气中燃烧”的实验后,他认为若收集一瓶氧气供硫粉在氧气中燃烧时使用,最好选择气体收集装置中的______(填装置序号),理由是______.通过查阅资料得知:①氨气(NH3)是一种密度比空气小且极易溶于水的气体,其水溶液称为氨水,显碱性;小刘同学想收集一瓶氨气,他应选择的收集装置是______(填字母编号);

(2)实验室常用加热氯酸钾与二氧化锰混合物的方法制取氧气,小芳发现,氯酸钾与氧化铜混合加热,也能较快产生氧气,于是进行如下探究:

提出猜想:除Mn02、CuO外,Fe203也可以作KCl03分解的催化剂.

完成实验:按下表进行实验,并测定分解温度(分解温度越低,催化效果越好).

实验编号    实验药品分解温度(℃)
  ①    KCl03    580
  ②  KCl03、Mn02质量比1:1)    350
  ③  KCl03、CuO(质量比l:1)    370
  ④  KCl03、Fe203(质量比1:1)    390
分析数据、得出结论:由实验______与实验④对比,证明猜想合理;实验所用的三种金属氧化物,催化效果最好的是______.

反思:若要证明Fe203是该反应的催化剂,还要验证它在化学反应前后的质量和______不变;质量相同的同种催化剂,颗粒大小可能影响催化效果,请设计实验方案进行验证:______.

考点:氧气的制取和收集催化剂和催化作用
题型:问答题

哮喘患者晚上服用麻黄碱可引起失眠()

题型:问答题

下列实验装置设计正确且能达到目的是(  )

A.

测定乙醇结构式

B.

滴定法测定硫酸的物质的量的浓度

C.

合成氨并检验氨的生成

D.

碘的CCl4溶液中分离I2,并回CCl4

题型:问答题
I was sitting at the bar of a local restaurant having __36__ and taking a break. A pretty girl who looked about 25 walked in and sat down in a booth(饭馆的小隔间) __37__ for her friend. It didn’t take long __38__ I saw she was trying to stay __39__ from other people’s gazes(注视) and my heart sank. You could see her hair was __40__ and, at such a young age, she was receiving chemo(化疗).
I sat there watching her trying to remain composed(镇静的) and she was having a __41__ time of it. I __42__ for her, imagining what it must be like to go through this and yet I know some of her __43__.
You see I __44__ my wife, the love of my life just a few short years ago and watched her slowly fade away. I needed to give a message of __45__ to this girl. But how? What could I do?
Then it __46__ to me! I called over her waitress and explained that I wanted to buy the girl and her friend’s lunch but I also told her not to tell her it was me. I also __47__ the waitress a note to give to the girl.
The note __48__ as follows:
“ Someone today thought you were beautiful; someone today thought your smile glowed __49__ excitement; someone today thought your eyes __50__ up the world; someone today cared and wanted you to know this. Enjoy the rest of your day, pretty young lady.”
About 15 minutes later, the young girl asked for her __51__ and I watched as she was told it was paid for. She asked why? Who? What for? The waitress simply handed her the note and __52__ to her the gentleman who did it left.
I watched as she slowly read the note. Her eyes tore up, for only a moment, and then came the smile! A huge, beautiful, hopeful smile! She lit up the room and then sat up straight, not __53__ who saw her.
It’s not __54__ we look or what we have; it’s not our houses or how many cars we have; nor is it how much money we can earn. It’s all about how much we care and what we do, __55__ it’s making someone feel pretty only for a moment.
小题1:
A.mealB.lunch 0C.teaD.breakfast
小题2:
A.searchingB.hopingC.lookingD.waiting
小题3:
A.soB.beforeC.afterD.until
小题4:
A.hiddenB.stubbornC.focused D.sighted
小题5:
A.falling inB.falling over C.falling outD.falling behind
小题6:
A.easyB.goodC.toughD.great
小题7:
A.sankB.achedC.trustD.puzzled
小题8:
A.ideaB.viewC.troubleD.pain
小题9:
A.leftB.deserted C.buried D.valued
小题10:
A.dreamB.hopeC.energyD.wish
小题11:
A.struckB.happenedC.occurred D.hit
小题12:
A.handedB.presentedC.providedD.brought
小题13:
A.toldB.spokeC.readD.wrote
小题14:
A.forB.onC.ofD.with
小题15:
A.toreB.litC.cheeredD.lifted
小题16:
A.billB.mealC.checkD.share
小题17:
A.explainedB.informedC.warnedD.reminded
小题18:
A.knowingB.ignoringC.riskingD.caring
小题19:
A.what B.whenC.whyD.how
小题20:
A.even thoughB.as thoughC.as ifD.if only
题型:问答题

下列关于我国养老保障制度的说法,正确的是()

A.国家基本养老金计划覆盖面广泛,保障程度较高

B.解决养老金缺口问题对国家基本养老金计划提出了一定压力

C.个人养老储蓄已经形成制度化

D.现有的养老保险体系对保证退休者退休生活品质还存在较大缺口

E.制定退休规划举足轻重,任重而道远

题型:问答题

已知某城镇失业人数为3200人,就业人数为36800人,则该城镇失业率为()

A、9%

B、8.7%

C、9.5%

D、8%

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