问题 选择题

已知NH3和HCl都能用来作喷泉实验。若在同温同压下用等体积烧瓶,一个收集满NH3,另一个收集满HCl气体,做喷泉实验,如图所示,喷泉实验停止后,两个烧瓶内溶液的关系是(不考虑溶质的扩散及静止时液面高度的影响)

A.溶质的物质的量浓度相同、溶质的质量分数不同

B.溶质的质量分数相同,溶质的物质的量浓度不同

C.溶质的物质的量浓度和溶质的质量分数都不同

D.溶质的物质的量浓度和溶质的质量分数都相同

答案

答案:A

题目分析:同温同压下用等体积烧瓶收集的NH3和HCl的物质的量相同,二者均易溶于水,所以溶液充满整个烧瓶,即所得溶液的体积相同,所以所得溶液中溶质的物质的量浓度相同;但等物质的量的NH3和HCl的质量不同,所以溶液中溶质的质量分数不同,答案选A。

完形填空

第二节完形填空(共20小题;每小题1分,满分20分)

阅读下面的短文,从短文所给的A、B、C和D四个选项中,选出可以填入空白处的最佳答案。

It was in my high school science class. I was doing a task in front of the classroom with my favorite shirt on.

A ___21___ came, “Nice shirt,” I smiled from ear to ear. Then another voice said, “That shirt belonged to my dad. Greg’s mother works for my family. We were going to ___22___ that shirt away, but gave it to her ___23___.” I was speechless. I wanted to hide.

I ___24___ the shirt in the back of the closet and told my mum what had happened. She then dialed her ___25___, “I will no longer work for your family,” she told him. That night, Mom told my dad that she couldn’t clean anymore; she knew her life’s ___26___ was something greater.

The next morning she ___27___ with the personnel manager at the Board of Education. He told her that without a proper education she could not teach. So Mom decided to ___28___ a university.

After the first year in college, she went back to the personnel manager. He said, “You are ___29___, aren’t you? I think I have a ___30___ for you as a teacher’s assistant. This opportunity deals with children who are mentally challenged with little or no chance of___31___.” Mom accepted the opportunity very ___32___.

For almost five years, as a teacher’s assistant, she saw teacher after teacher give up on the children and quit, feeling ___33___. Then one day, the personnel manager and the principal ___34___ in her classroom. The principal said, “We have watched how you ___35___ the children and how they communicate with you and admire your hard-working ___36___ over the last five years. We are all in agreement that you ___37___ be the teacher of this class.”

My mom spent more than 20 years there. ___38___ her career, she was voted Teacher of the Year. All of this came about because of the ___39___ comment made in the classroom that day when I was in my high school. Mom showed me how to handle ___40___ situations and never give up.

21. A. noise    B. voice  C. sound  D. tune

22. A. get       B. take    C. carry   D. throw

23. A. otherwise     B. anyhow      C. instead       D. actually

24. A. settled  B. pushed       C. picked D. put

25. A. teacher B. employer    C. director      D. adviser

26. A. purpose       B. encouragement     C. process       D. victory

27. A. went     B. met     C. worked      D. stayed

28. A. visit     B. continue     C. attend D. prepare

29. A. serious  B. fortunate    C. careful       D. responsible

30. A. career   B. duty    C. position      D. part

31. A. learning       B. judging     C. obeying      D. imagining

32. A. patiently      B. eagerly       C. successfully       D. skillfully

33. A. upset    B. frightened  C. guilty  D. ashamed

34. A. looked up    B went up       C. took up      D. showed up

35. A. believe B. protect       C. treat    D. receive

36. A. spirit    B. intention    C. idea    D. attempt

37. A. must     B. would C. might  D. should

38. A. At B. During       C. On      D. With

39. A. worthless     B. thoughtless C. hopeless     D. helpless

40. A. challenging  B. different     C. dangerous   D. strange

单项选择题