问题 选择题

下列过程发生化学变化的是

A.酒香扑鼻

B.火药爆炸

C.干冰升华

D.用金刚石切割玻璃

答案

答案:B

题目分析:物理变化和化学变化的根本区别在于是否有新物质生成,如果有新物质生成,则属于化学变化;反之,则是物理变化。A、酒香扑鼻是分子的运动,没有生成了新物质,属于物理变化,B、火药爆炸是火药在有限空间急速燃烧引起,有生成了新物质,属于化学变化,C、干冰升华式由固态变为气态的过程,没有生成了新物质,属于物理变化,D、用金刚石切割玻璃是物质形状的改变,没有生成了新物质,属于物理变化,故选B

完形填空

During my second year of middle school, our teacher gave us a test. I studied hard and   __46  well in all the subjects, so the questions were not difficult for me.  47  I stopped when I read the last one:“What is the   48  of the woman that cleans the school?”
Of course this was a joke. I saw the cleaning woman every day. She was short and about 60 years old. She had dark hair. But   49  would I know her name? I had never talked    __50 her before. In fact, I had never even thought about talking to her. I started to feel rather guilty(惭愧的).Finally, I   51  my paper, without finishing the last question.
Before the class ended, one student asked, “Will be last question count(计入) toward   __52  grade?” “Of course,” the teacher said, “In your life, you will meet many people. All are important. They deserve(值得) your attention and care, even if you just   53  and say hello to them.”
I’ve never forgotten that   54 _. I should get to know all of the people who work and live around me. That was, perhaps, the most   55  lesson of my life. Later, I learned that the cleaning woman’s name was Dorothy.
小题1:
A.becameB.madeC.gotD.did
小题2:
A.SoB.ButC.OrD.And
小题3:
A.addressB.numberC.nameD.hobby
小题4:
A.whereB.howC.whatD.when
小题5:
A.withB.aboutC.forD.back
小题6:
A.gave awayB.took awayC.handed inD.handed out
小题7:
A.weB.usC.oursD.our
小题8:
A.shoutB.smileC.cryD.laugh
小题9:
A.lessonB.storyC.fictionD.report
小题10:
A.difficultB.interestingC.importantD.exciting
填空题