某化学兴趣小组设计了如右图所示实验装置,进行了以下实验。 (1)先打开K1,关

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问题:

某化学兴趣小组设计了如右图所示实验装置,进行了以下实验。

(1)先打开K1,关闭K2和K3,从长颈漏斗向A 中加入足量的稀盐酸。此时装置B

中发生反应的化学方程式为       ,打开K1的目的是           

(2)然后关闭K1和 K3,打开K2,将胶头滴管中的浓氢氧化钠溶液挤入锥形瓶中。

稍后打开K3,此时装置C和D中的现象分别是                     

装置C中发生反应的化学方程式为        。若在(2)实验过程中没有关闭K1,其它操作相同,则装置B的现象不同点是        

考点:实验室制取和收集气体的思路二氧化碳的性质实验化学实验数据的分析家庭小实验、趣味实验
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一个马铃薯是生物体的一个部分。                             (   )

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列宁称马克思.恩格斯是“19世纪人类三个最先进国家中三种主要思潮的继承人和天才的完成者”。这里“三种重要思潮”指的是(    )

①德国的古典哲学②英国的古典政治经济学③法国的空想社会主义④法国的启蒙思想

A.②③④

B.①②④

C.①③④

D.①②③

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My partner and I were staying in Beruwela on the Southwest coast of Sri Lanka when the tsunami(海啸) hit. We   1  from the first floor of our hotel. At that time, a wall of water swept in and tore the ground floor apart underneath us.   2  to be moved out to Colombo was very frightening because everyone was afraid that another and possibly bigger   3  would come. At one stage we heard that another wave was coming and there was   4 . Surprisingly, a fleet of small vehicles driven by local people arrived outside the hotel and we just  5  a minibus.
We were taken up a hill to a place of   6  where we were welcomed by a family who told us that we could stay as   7  as we needed to. Among all this death and   8 , these people were trying to help us! We were shown to the local Mosque where hundreds of locals were cooking, collecting and distributing food and supplies for those less   9 . In the three days we were waiting to leave, we saw many examples of ordinary Sri Lankans, many of whom had lost friends,   10  and livelihoods(生计,谋生方式), trying to help others who were worse off. It was a very moving experience.
We have since been   11  the family who took us in and they are saying that what their country needs most urgently is practical help, doctors, nurses and medicines, helping to   12   roads and rebuilding electricity and water supplies. These people would have done anything to help us, it is time for the British Government to do more to help them. 
小题1:
A.heardB.watchedC.learntD.moved
小题2:
A.TellingB.ForcingC.WaitingD.Ordering
小题3:
A.waveB.floodC.hurricaneD.water
小题4:
A.panicB.peaceC.silenceD.violence
小题5:
A.looked intoB.turned toC.jumped intoD.broke into
小题6:
A.safetyB.warmthC.goodnessD.dreams
小题7:
A.wellB.farC.soonD.long
小题8:
A.kindnessB.happinessC.loveD.destruction
小题9:
A.carefulB.fortunateC.dependentD.energetic
小题10:
A.childrenB.expertsC.familyD.relatives
小题11:
A.in honor ofB.by way ofC.in contact withD.on behalf of
小题12:
A.makeB.clearC.cleanD.build
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数控机床接口是指()与机床及机床电气设备之间的电气连接部分。

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下列选项中,哪些属于我国当代法的正式渊源( )

A.行业协会制定的行业标准

B.最高人民法院对地方法院的请示所做的批复

C.某民族自治县制定的单行条例

D.公安部制定的某行政规章

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