问题 选择题

今有组成为CH4O和C3H8O的混合物,在浓H2SO4作用下进行脱水反应,最多可产生有机物是  

A.4种

B.5种

C.6种

D.7种

答案

答案:D

考查点:①醇的脱水反应:分子间脱水和分子内脱水;②同分异构体。CH4O只能代表甲醇,CH3OH;C3H8O可代表两种醇,CH3CH2CH2OH(1-丙醇)和(2-丙醇)。

分子间脱水:①CH3OH+CH3CH2CH2OH→CH3-O-CH2CH2CH3+H2O

②CH3OH+

③CH3—OH+CH3—OH→CH3—O—CH3+H2O

④CH3CH2CH2OH+CH3CH2CH2OH→CH3CH2CH2—O—CH2CH2CH3+H2O

分子内脱水:CH3OH不能发生分子内脱水

⑦CH3CH2CH2OH→CH3—CH=CH2+H2O

→CH3—CH=CH2+H2O

可见生成的烯烃相同。

综上所述,脱水后最多可产生7种有机物。

阅读理解

“My dear lady,” says Holmes. “You’re shivering. Are you old? Do you want a cup of hot tea?”

“I’m not cold,” the woman replies, “I fear for my life!”

“We are here to help you. Don’t worry about anything. I don’t know you. But I know many things about you. For example, I know how you travel. You came to London by train. You also ride to the train station on a horse-drawn wagon(马车).”

“Why, yes. You’re right. But how do you know these things?”

“ I see a return ticket in your glove. I see fresh mud on the left arm of your dress. Now tell us your problem.”

“My name is Helen Stoner,” she states, “ My mother and father are dead. I am living with my stepfather, Dr Grimesby Roylott. He comes from a rich family. But they are no longer rich. They have nothing except a small piece of land and a huge old house. We are living in the house. Dr Roylott is using my mother’s money for expenses(开支). Part of it was for my sister and me. It was for our marriages.”

Holmes is sitting in his chair. His eyes are closed. He is listening carefully to Helen’s story. He hears every detail.

Helen continues. “My stepfather has no friends. He fights with everyone. He is strong and gets angry quickly. Everyone is afraid of him.”

“He has no friends at all?” asks Holmes.

“No. He talks to no one except the gypsies. They are poor people who travel from place to place. A band of gypsies is staying on our land right now.”

“Are you and your sister afraid of the gypsies?”

“My dear Mr Holmes. You are making me so sad. My sister is dead. That is why I am standing here in this room.”

小题1:Paragraph 6 beginning with “My name is …” is mostly about_______________.

A.Helen’s dead sister

B.Helen’s trip to London

C.the house Helen lives in

D.Helen’s stepfather and the family小题2:What is Holmes doing while Helen is telling her story?

A.Walking slowly

B.Listening carefully

C.standing sadly

D.Writing quickly小题3:Which of the following can best describe the gypsies according to the passage?

A.They are very rich

B.They are afraid of other people

C.They live on a horse-drawn wagon

D.They move from one place to another小题4:The passage is probably from __________.

A.a novel

B.a guide

C.a poem

D.an advertisement

填空题