问题 选择题

下列除去括号内杂质的有关操作方法正确的是(  )

①CO2(SO2):饱和NaHCO3的溶液,洗气.②KCl(AlCl3):氨水,过滤.③C2H6(C2H4):溴的CCl4溶液,洗气.④水(碘):酒精,萃取分液.⑤苯(甲苯):分馏.

A.①②③

B.③④⑤

C.②④

D.①③⑤

答案

①SO2与饱和NaHCO3的溶液发生反应:SO2+2NaHCO3═+Na2SO3H2O+2CO2,CO2不能与饱和NaHCO3的溶液发生反应,所以可通过饱和溶液洗气以除去SO2气体,故①正确;

②氢氧化铝不溶于弱碱,AlCl3与氨水反应方程式为:AlCl3+3NH3•H2O=Al(OH)3↓+3NH4Cl,产生了新的杂质NH4Cl,故不能用加入氨水再过滤的方法除去AlCl3,故②错误;

③C2H4能与溴水发生加成反应生成1,2-二溴乙烷,得到纯净的C2H6,应通入溴水中除去杂质,故③正确;

④碘在水中的溶解度大于在水中的溶解度,但酒精易溶于水,不能用萃取分液的方法除去杂质,故④错误;

⑤苯和甲苯是互不相溶的两种液体,故可用分馏的方法将两者分开,故⑤正确;

故选:D.

阅读理解

We were standing at the top of a church tower. My father had brought me to this spot in a small town not far from our home in Rome. I wondered why.

"Look down, Elsa," Father said. I gathered all my courage and looked down. I saw the square in the center of the village. And I saw the crisscross (十字形) of twisting, turning streets leading to the square. "See, my dear," Father said gently. "There is more than one way to the square. Life is like that. If you can't get to the place where you want to go by one road, try another."

Now I understood why I was there. Earlier that day I had begged my mother to do something about the awful lunches that were served at school. But she refused because she could not believe the lunches were as bad as I said.

When I turned to Father for help, he would not help. Instead, he brought me to this high tower to give me a lesson. By the time we reached home, I had a plan.

At school the next day, I secretly poured my lunch soup into a bottle and brought it home. Then I asked our cook to serve it to Mother at dinner. The plan worked perfectly. She swallowed one spoonful and sputtered, "The cook must have gone mad! "Quickly I told what I had done, and Mother said firmly that she would take up the matter of lunches at school the next day!

In the years that followed I often remembered the lesson Father taught me. I began to work as a fashion designer two years ago. I wouldn't stop working until I tried every possible means to my goal, Father's wise words always remind me that there is more than one way to the square.

小题1:

What did the author want her mother to do earlier that day? _______           

A.Do something delicious for lunch.

B.Ask the father to taste her awful lunch.

C.Dismiss the mad cook.

D.Speak to the school about lunch.小题2:

The underlined sentence in the fifth paragraph means ______ . 

A.the cook agreed to serve the soup to Father

B.the matter of lunch hasn’t been settled

C.her father persuaded her mother successfully

D.the method the author thought of was effective小题3:

By sharing her own experiences, the author tries to tell us________.   

A.when one road is blocked, try another

B.how bad the lunch of her school is

C.how wise her father is

D.about the church rower' near her home

填空题