题干

某兴趣小组利用下列实验装置进行探究实验.

根据要求回答下列问题:

(1)如图1装置中长颈漏斗的作用有导气、____ .

(2)利用装置C可以证明SO2具有漂白性,C中盛放的溶液是____ ;若要证明其漂白作用是可逆的,还需要的操作是____  .

(3)通过观察D中现象,即可证明SO2具有氧化性,D中盛放的溶液可以是____ .

a.NaCl溶液b.酸性KMnO4c.FeCl3d.Na2S溶液

(4)研究小组发现B中有白色沉淀生成,若往B中加入过量稀盐酸,沉淀不溶解.沉淀物的化学式是____ .

(5)为进一步验证B中产生沉淀的原因,研究小组进行如下两次实验:

实验i:另取BaCl2溶液,加热煮沸,冷却后加入少量苯(起液封作用),然后再按照上述装置进行实验,结果发现B中沉淀量减少,但仍有轻微浑浊.

实验ii:用如图2F装置代替上述实验中的A装置(其他装置不变),连接后往装置F中通入气体X一段时间,再加入70%H2SO4溶液,结果B中没有出现浑浊.

①“实验i”中煮沸BaCl2溶液的目的是____ ;

②气体X不可以是____ (填序号).

a.CO2       b.O3     c.N2     d.NO2

③B中形成沉淀的原因是(用化学方程式表示): 

____ 

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答案(点此获取答案解析)

\u9632\u5012\u5438,\u54c1\u7ea2\u6eb6\u6db2,\u53d6\u5c11\u91cf\u892a\u8272\u540e\u7684\u6eb6\u6db2\u4e8e\u8bd5\u7ba1\u4e2d\u52a0\u70ed,d,BaSO4,\u9664\u53bbBaCl2\u6eb6\u6db2\u4e2d\u7684O2,bd,2SO2

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    There are two basic ways to see growth:one as a product,the other as a process.People have generally viewed personal growth as an external(外在的)result or a product that can easily be identified and measured.The worker who gets a rise,the student whose grades improve,the foreigner who learns a new language—all these examples of people who have measurable results to show for their efforts.

    By contrast(对照),the process of personal growth is much more difficult to determine,since it is a journey and not the specific signposts or landmarks along the way.The process is not the road itself,but the attitudes,feelings people have,and their caution or courage,as they meet with new experiences and unexpected difficulties.In this process,the journey never really ends;there are always new ways to experience the world,new ideas to try,new challenges to accept.

    In order to grow,to travel new roads,people need to have a willingness to take risks,to face the unknown,and to accept the possibility that they may“fail”at first.How we see ourselves as we try a new way of being is necessary for our ability to grow.Do we see ourselves as quick and curious?If so,we tend to take more chances and be more open to unfamiliar experiences.Do we think we're shy and indecisive?Then our sense of fear can cause us to hesitate,to move slowly,and we think we are slow to adapt(适应)change or that we're not smart enough to deal with a new challenge.Then we are likely to take a more passive role or not try at all.

    These feelings of insecurity(不安全)and self­doubt are both unavoidable and necessary if we are to change and grow.If we protect ourselves too much,then we stop growing.We become trapped inside a shell of our own making.

____, ②____,③____,④____,⑤____,

____,⑦____,⑧____,⑨____,⑩____,