题干

Everyone, be sure to be honest! You can't get away __________ cheating in the exam.

A:from

B:with

C:off

D:o

上一题 下一题 0.0难度 选择题 更新时间:2017-06-05 12:17:22

答案(点此获取答案解析)

B

同类题1

请阅读下面短文,根据短文内容,从方框内所给的选项中选出能填入空白处的最佳选项,使短文意思通顺。选项中有一项为多余项。

    What is life's greatest gift? It is choice. Choice is the ability to choose some actions from a set of things to achieve a goal. ____ The reason is that it turns us from dumb animals into artists. Choise becomes the tool we use to sculpt (雕刻) our life. The tool doesn't come free, however, for the price of choice is responsibility. ____It is enjoyment.

    Choice is power. Choice is at the heart of life. It's the creative power of life. Life is awlays changing and we have to make lots of choices. ____ We often need to check where we are on our journey. We need to ask questions: Am I moving closer to my goals? If not, what action will I take now to make myself realize my goals?

____ And our life becomes more convenient or comfortable because of them. For example, you decide which stores to shop at and which bus station to go to. But the decisions that we make to sculpt our lives are much more important than deciding where to shop. The more we understand the difference between small and big decisions. The more pleasure we wil get.

    Life is like a chess game. ____ All chess lovers realize that it isn't necessary to win to enjoy the game. Make the best moves you can under the conditions. Then you can enjoy your life.

A. Why is choice so great?

B. The pleasure is in the playing.

C. In fact, we have to make choices every day.

D. But when we accept and carry it out, we get a great return.

E. Because making righr choices is more important than working hard.

F. Every choice we make leads us closer to or father from our goals.

同类题4

某研究小组在实验室探究氨基甲酸铵(NH2COONH4)分解反应平衡常数和水解反应速率的测定.

(1)将一定量纯净的氨基甲酸铵置于特制的密闭真空容器中(假设容器体积不变,固体试样体积忽略不计),在恒定温度下使其达到分解平衡:NH2COONH4(s)⇌2NH3(g)+CO2(g).

实验测得不同温度下的平衡数据列于下表:

温度(℃)

15.0

20.0

25.0

30.0

35.0

平衡总压强(kPa)

5.7

8.3

12.0

17.1

24.0

平衡气体总浓度(×10﹣3mol/L)

2.4

3.4

4.8

6.8

9.4

①可以判断该分解反应已经达到化学平衡的是____ 

A.2v(NH3)=v(CO2)B.密闭容器中总压强不变

C.密闭容器中混合气体的密度不变D.密闭容器中氨气的体积分数不变

②根据表中数据,列式计算25.0℃时的分解平衡常数:____ 

③取一定量的氨基甲酸铵固体放在一个带活塞的密闭真空容器中,在25℃下达到分解平衡.若在恒温下压缩容器体积,氨基甲酸铵固体的质量____ (填“增加”、“减小”或“不变”).

④氨基甲酸铵分解反应的焓变△H ____ 0,熵变△S____ 0(填>、<或=).

(2)已知:NH2COONH4+2H2O⇌NH4HCO3+NH3•H2O.该研究小组分别用三份不同初始浓度的氨基甲酸铵溶液测定水解反应速率,得到c(NH2COO﹣)随时间变化趋势如图所示.

⑤计算25℃时,0~6min氨基甲酸铵水解反应的平均速率____ 

⑥根据图中信息,如何说明水解反应速率随温度升高而增大:____