问题 填空题

(16分)某实验小组用下列装置进行乙醇催化氧化的实验。

⑴实验过程中铜网出现红色和黑色交替的现象,请写出相应的化学方程式

                                 、                                    

在不断鼓入空气的情况下,熄灭酒精灯,反应仍能继续进行,说明该反应是     反应(填“吸热”或“放热”)。

⑵甲和乙两个水浴作用不相同。甲的作用是           ;乙的作用是                

⑶反应进行一段时间后,于试管a中能收集到不同的物质,它们是乙醇、乙醛和           (填一种物质名称即可)。

集气瓶中收集到的气体的主要成分是           (填物质名称或化学式)。

⑷若试管a中收集到的液体用紫色石蕊试纸检验,试纸显红色,说明液体中还含有     

(填物质名称或化学式)。要除去该物质,可现在混合液中加入    (填写字母)。

a.氯化钠溶液     b.苯     c.碳酸氢钠溶液    d.四氯化碳

然后,还要通过      (填试验操作名称)才能得到较纯的乙醛。

答案

(16分)

⑴ 2Cu+O22CuO (2分)CH3CH2OH+CuOCH3CHO+Cu+H2O(2分)放热(1分)⑵加热 (1分)冷凝 (1分) ⑶水(1分),氮气(2分) 

⑷乙酸(2分) c(2分)  蒸馏(2分)

选择题
阅读理解

One stormy night many years ago, an elderly man and his wife entered the hall of a small hotel in Philadelphia. Trying to get out of the rain, they came to the front desk hoping to get some shelter for the night.

“Could you possibly give us a room here?” the husband asked.

The clerk, a friendly man with a winning smile, looked at the couple and explained that there were three conventions in town.“All of our rooms are taken,” the clerk said.“But I can’t send a nice couple like you out into the rain at one o’clock in the morning. Would you perhaps be willing to sleep in my room? It’s not exactly a suite, but it will be good enough to make you folks comfortable for the night.”

When the couple declined, the young man pressed on.“Don’t worry about me; I’ll make out just fine.” the clerk told them. So the couple agreed.

As he paid his bill the next morning, the elderly man said to the clerk,“You are the kind of manager who should be the boss of the best hotel in the United States. Maybe someday I’ll build one for you.” The clerk looked at them and smiled. The three of them had a good laugh. As they drove away, the elderly couple agreed that the helpful clerk was indeed exceptional, as finding people who are both friendly and helpful isn’t easy.

Two years passed. The clerk had almost forgotten the incident when he received a letter from the old man. It recalled that stormy night and enclosed a round—trip ticket to New York, asking the young man to pay them a visit.

The old man met him in New York, and led him to the corner of Fifth Avenue and 34th street. He then pointed to a great new building there, a pale reddish stone, with turrets and watchtowers thrusting up to the sky.“That,” said the older man,“is the hotel I have just built for you to manage.”“You must be joking,” the young man said.“I can assure you I am not,” said the older man, a sly smile playing around his mouth.

The older man’s name was William Waldorf Astor, and that magnificent structure was the original Waldorf—Astoria Hotel. The young clerk who became its first manager was George C.Boldt. This young clerk never foresaw the turn of events that would lead him to become the manager of one of the world’s most glamorous hotels.

小题1:The purpose of the author writing this story is to_______.

A.give people a good laugh

B.cover some facts

C.promote the business of Waldorf—Astoria Hotel

D.deliver a lesson小题2:Which of the statements about the story is NOT true?

A.The story took place at about one a.m..

B.The old couple was too poor to afford a luxurious room.

C.The clerk was willing to help those in need.

D.The clerk received an unexpected invitation from the old man.小题3:The underlined word “conventions” in Para.3 can be replaced by_______?

A.rooms

B.suites

C.meetings

D.hotels小题4:Which of the following proverbs suits the story the best?

A.Every little thing helps.

B.Make hay while the sun shines.

C.Man proposes; God disposes(处理,决定).

D.One good turn deserves another.