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【简答题】
实验室有4瓶没有标签的无色溶液，甲、同学对溶液的鉴别进行了探究． （1）据老师说，这4瓶无色溶液可能是Na 2 CO 3 、CuSO 4 、NaOH、Ca（OH） 2 和稀HCl溶液中的4种，同学们思考后，当即否定了CuSO 4 溶液，原因是______． （2）甲组同学把4种无色溶液分别贴上A、B、C、D标签，按以下步骤进行探究： 第1步：取4支试管，分别加入少量的A、B、C、D溶液，然后依次滴加稀盐酸， 实验现象如下： 溶液 A B C D 现象 无明显现象 无明显现象 产生气泡 无明显现象 实验解释：C溶液中发生反应的方程式为：______． 第2步：取3支试管，分别加入少量的A、B、D溶液，然后依次通入第一步C溶液中产生的气体，可观察到A溶液中有白色沉淀，B、D溶液中均无明显现象． 实验结论：A是______溶液． 第3步：用两支玻璃棒分别蘸B、D溶液在酒精灯上加热，观察到蘸有B溶液的玻璃棒上蒸干后没有白色固体，蘸有D溶液的玻璃棒上有白色固体析出， 实验结论：B是______，D是______溶液． （3）同学经过讨论后认为，不需外加试剂也能鉴别出四种溶液．各自分别做了如下实验： 同学 实验操作 实验现象 结论 小娟 用3支试管，各取少量三种溶液，分别滴加另一种溶液． 一支试管溶液中有气泡放出，其余两支试管溶液中无现象． 所滴加的溶液是稀盐酸． 小刚 一支试管溶液中有白色沉淀析出，其余两支试管溶液中无现象． 所滴加的是Na 2 CO 3 溶液． 三支试管溶液中现象． 所滴加的是NaOH溶液． 三位同学经过交流后发现______同学的结论是错误的，所滴加的溶液应该是______溶液，由此鉴别出了四种溶液．
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【单选题】The beam that is ______by a laser differs in several ways from the light that comes out of a flashlight.
A.
emitted
B.
transported
C.
motivated
D.
translated
【单选题】听力原文：M: What a wonderful party! Everyone is having a good time. W: If only the children were here! Q: What is implied in the conversation? (13)
A.
The children enjoyed themselves.
B.
The children didn't come to the party.
C.
The children were giving a lot of fun in the party.
D.
The children were not behaving themselves in the party.
【单选题】听力原文：M：What do you think of biology? W：It's given me a hard time，though it is not as difficult as math． Q：What call we learn about the woman from this conversation? (17)
A.
She is going to give up biology.
B.
She spends half of her time on biology.
C.
To her, biology is difficult, but math is not.
D.
To her, math is even more difficult than biology.
【单选题】听力原文：M：What do you think of biology? W：It's given me a hard time，though it is not as difficult as math． Q：What Can we learn about the woman from this conversation? (17)
A.
She is going to give up biology.
B.
She spends half of her time on biology.
C.
To her, biology is difficult, but math is not.
D.
To her, math is even more difficult than biology.
【单选题】This morning m y mother asked me__.
A.
why he is not here
B.
where Julia went last weekend
C.
what time is it
D.
how did my brother do it
【简答题】请将刚刚的对话翻译成中文。 A: Hello, Doctor Deng's office. B: Hello, I need to make an appointment. A: What do you need to see the doctor about? B: I have a toothache. My cheek is swollen and I can't eat anything....
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