题干

实验室用溴和苯反应制取溴苯,得到粗溴苯后,要用如下操作精制:①蒸馏②水洗③用干燥剂干燥④10﹪NaOH溶液洗⑤水洗,正确的操作顺序是

A:①②③④⑤

B:②④⑤③①

C:④②③①⑤

D:②④①⑤③

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B

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    A little boy invited his mother to attend his school's first teacher-parent meeting. To the little boy's dismay(沮丧), his mother said she would go. This would be the first time that his classmates and teachers met his mother and he was embarrassed by her appearance. There was a severe(严重的) scar (伤疤) that covered nearly the whole right side of her face. The boy never wanted to talk about why or how she got the scar.

    At the meeting, the people were impressed by the kindness of his mother with the scar, but the little boy was still embarrassed and hid himself from everyone. However, he could hear clearly the conversation between his mother and the teacher.

     “How did you get the scar on your face?” the teacher asked.

    The mother replied, “When my son was a baby, he was in a room that caught on fire. Everyone was too afraid to go in because the fire was out of control, but I went in. As I was running towards his bed, I saw a burning wood falling down and I placed myself over him trying to protect him. I was knocked to be unconscious(无知觉的), but luckily, a fireman came in and saved both of us.” She touched the burned side of her face. “This scar will be forever, but until today, I have never regretted doing what I did.”

    When the little boy heard this, he couldn't help running towards his mother with tears in his eyes. He hugged her and felt his mother was greater than anyone. He held her hand tightly for the rest of the day.