问题 实验题

某校化学研究性学习小组的同学在学习了氨气的性质后讨论:运用类比的思想,既然氨气具有还原性,能否像H2那样还原CuO呢?请你参与该小组的探究活动并回答下列问题:

(1)写出实验室制取氨气的化学方程式:____________________。

(2)有同学类比排饱和食盐水收集氯气的方法,想用排饱和氯化铵溶液的方法收集氨气。你认为他能否达到目的?_________(填“能”或“否”)。

(3)该小组某同学设计了下图所示的实验装置(夹持及尾气处理装置未画出),探究氨气的还原性。

该装置在设计上有一定缺陷,为保证实验结果的准确性,对该装置的改进措施是_______________

(4) 利用改进后的装置进行实验,观察到CuO变为红色物质,无水CuSO4变蓝色,同时生成一种无污染的气体。写出氨气与CuO发生反应的化学方程式:_____________________

(5)若将改进后的装置中的A换成下图中的X,能否顺利完成实验?__________ (填“能”或“否”)。小组中的某同学将A换成了下图中的Y,结果无水CuSO4变蓝色,据此削断氨气与CuO发生了反应。你以为他的结论是否严谨?_______ (填“是”或“否”)。原因是____________________。

答案

(1)Ca(OH)2+2NH4ClCaCl2+2NH3↑+2H2O

(2)否

(3)在A和B之间加一个装有碱石灰的U形管

(4)2NH3+3CuO3Cu+N2+3H2O

(5)能;否;H2也能还原CuO,且产物能使无水CuSO4变蓝

阅读理解

阅读理解。

     When I was growing up, I was embarrassed to be seen with my father. He was badly crippled (跛脚),

and when we would walk together, his hand on my arm for balance, people would stare and I would be

ashamed of the unwanted attention. If ever noticed or bothered, he never let on.

     It was difficult to walk together-and because of that, we didn't say much as we went along. But as we

started out, he always said, "You set the pace. I will try to follow you."

     Our usual walk was to or from the subway, which was how he got to work. He went to work even in

bad weather. He almost never missed a day, and would make it to the office even if others could not. It was

a matter of pride for him.

     When snow or ice was on the ground, it was impossible for him to walk, even with help...Such times

my sister or I would pull him through the streets of Brooklyn, N. Y., on a child's sleigh to the subway entrance.

Once there, he would try to grasp handrail until he reached the lower steps that the warmer tunnel air kept

ice free. In Manhattan the subway station was the basement of his office building, and he would not have to

go outside again until we met him in Brooklyn on his way home.

     When I think of it now, I am surprised at how much courage it must have taken for a grown man to suffer

from shame and disability. And I am also surprised at how he did it-without bitterness or complaint.

     He never talked about himself as an object of pity, nor did he show any envy of the more fortunate or able. What he looked for in others was a "good heart", and if he found one, the owner was good enough for him.

     Now that I am older, I believe that is a proper standard by which to judge people, even though I still don't

know exactly what a "good heart" is. But I know the times I don't have one myself.

     He has been away for many years now, but I think of him often. I wonder if he sensed my reluctance to

be seen with him during our walks. If he did, I am sorry I never told him how sorry I was, how unworthy I

was, how I regretted it. I think of him when I com- plain about my troubles, when I am envious of another's

good for-tune, when I don't have a "good heart".

1. How did the man treat his father when he was young?

A. He helped his father happily.

B. He never helped his father.

C. He helped his father, but not very happily.

D. He only helped his father take a walk after supper.

2. As a disabled man, his father ____. 

A. didn't work very hard

B. didn't go to work from time to time

C. hated those who had good fortune

D. was happy and satisfied, and never lost hope

3.What does the underlined word "reluctance" mean in the article? It means ____.

A. anger

B. sadness

C. happiness

D. unwillingness

4. How did the father get to work usually?

A. By subway.

B. By bus.

C. By wheelchair.

D. By bike.

选择题