科学探究是奇妙的过程。在一次实验中,小明不小心把硫酸铜溶液滴加到了盛有5%H2O

题型:实验题

问题:

科学探究是奇妙的过程。在一次实验中,小明不小心把硫酸铜溶液滴加到了盛有5%H2O2的溶液的试管中,立即有大量的气泡产生。硫酸铜溶液中含有三种粒子(H2O、SO42-、Cu2+),小明想知道硫酸铜溶液中的哪种粒子能使双氧水分解的速率加快。请你和小明一起通过下图所示的三个实验完成这次探究活动,并填写空白。

(1)你认为最不可能的是哪一种粒子________,理由是___________________。

(2)检验实验①产生的气体的方法是____________。

(3)要证明另外两种粒子能否加快双氧水分解的速率,还需要进行实验②和③;在实验②中加入稀硫酸后,无明显变化,证明________不起催化作用;在实验③中加入___________后,会观察到大量的气泡,证明起催化作用的是_________________。

(4)小明如果要确定硫酸铜是催化剂,还须通过实验确认它在化学反应前后______________。

考点:盐的性质设计实验和科学探究
题型:实验题

图中,被称为“骑在羊背上的国家”、“坐在矿车上的国家”的是(    )

题型:实验题
Most people have no idea of the hard work and worry that go into the collecting of those interesting birds and animals that they pay to see in the zoo. One of the questions that is always asked of me is 36  I became an animal collector in the first 37  .The answer is that I have always been interested in animals and zoos. According to my parents, the first word I was able to say with any 38    was not the traditional “mamma” or “daddy”,39   the word “zoo”, which I would 40  over and over again with a exciting 41   until someone, in groups to 42  me up, would take me to the zoo. When I 43  a little older, we lived in Greece and I had a great 44 of pets, ranging from owls(鹰) to seahorses, and I spent all my spare time 45the countryside in search of fresh specimens to 46  to my collection of pets.
47 on I went for a year to the City Zoo, as a student 48  , to get experience of the large animals, such as lions, bears, bison and ostriches,49  were not easy to keep at home. When I left, I 50  had enough money of my own to be able to 51  my first trip and I have been going 52  ever since then. Though a collector's job is not an easy one and is full of  53  ,it is certainly a job which will appeal 54  all those who love animals and 55 . 
小题1:
A.howB.whereC.whenD.whether
小题2:
A.regionB.fieldC.placeD.area
小题3:
A.clearnessB.emotionC.feelingD.affection
小题4:
A.exceptB.butC.except forD.but for
小题5:
A.reciteB.recognizeC.readD.repeat
小题6:
A.volumeB.noiseC.voiceD.pitch
小题7:
A.closeB.shutC.stopD.comfort
小题8:
A.grewB.was growingC.growD.grown
小题9:
A.manyB.amountC.numberD.much
小题10:
A.living B.seeingC.likingD.exploring
小题11:
A.increase B.includeC.addD.enrich
小题12:
A.later B.furtherC.thenD.farther
小题13:
A.servantB.keeperC.memberD.assistant
小题14:
A.whoB.theyC.of whichD.which
小题15:A successfully    B. gladly       C. nearly       D. luckily 
小题16:
A.payB.finance C.allowD.provide
小题17:
A.normally B.oftenC.usuallyD.regularly
小题18:
A.unhappiness B.sorrowsC.excitement D.disappointments
小题19:
A.forB.withC.toD.from
小题20:
A.voyage B.travelC.journeyD.Trip
题型:实验题

下列关于建设工程项目施工图预算对建设单位的作用叙述正确的有( )。

A.施工图预算是招标投标的重要基础

B.施工图预算是确定投标报价的依据

C.施工图预算是拨付进度款及办理结算的依据

D.施工图预算是建设单位在施工期间安排建设资金计划的依据

E.施工图预算是审定招标工程标底的重要依据

题型:实验题

被称为第二肩关节的是:()

A.胸锁关节

B.肩锁关节

C.肩峰下区

D.肩胛胸壁关节

E.肩肱关节

题型:实验题

下列不属于建立身体美感三大秘诀的是()

A.短期:穿着适宜的服装

B.中期:维持良好的姿势

C.长期:锻炼健美的身材

D.中长期:正确的站姿

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