问题 问答题

在如图I装置中,烧瓶中充满干燥的气体a,将滴管中的b液体挤入烧瓶内,轻轻振荡烧瓶,然后打开弹簧夹,烧瓶内气体a由于极易溶解于液体b,使烧瓶内气压小于外界大气压,从而把烧杯内的液体压回烧瓶,呈喷泉状喷出,最终几乎充满烧瓶.则

(1)a和b分别是(______ )

A.N2,H2O              B.CO2,浓NaOH

C.NH3,盐酸            D.O2,H2O

(2)写出上述能进行化学反应的一个化学方程式______.

(3)某学生设计了如图Ⅱ的喷泉实验:

①在图中的锥形瓶里,分别加入足量的下列物质,反应后能产生喷泉的是(______)

A.Cu和稀盐酸         B.HCl溶液和NaOH溶液

C.Fe2O3和稀硫酸       D.Zn和稀硫酸

②在图II的锥形瓶外放一水槽,向锥形瓶加入酒精,水槽中加入冷水后,再分别加入足量的下列物质,可产生喷泉的是(______ )

A.生石灰    B.硫酸铜    C.浓硫酸 D.硫酸钾.

答案

(1)A和D选项中,N2和O2与水不反应,又不溶于水,烧瓶内的压强与外界大气压强相等,不会形成喷泉,故不选AD;

B选项中CO2与NaOH能发生反应,C选项中NH3与盐酸能发生反应,气体被吸收进溶液中,烧瓶内压强减小,同外界大气压产生压强差,所以形成喷泉,故选:BC;

(2)碱能与非金属氧化物反应生成盐和水,故答案为:2NaOH+CO2=Na2CO3+H2O.

或①氨气与水生成氢氧化铵,NH3+H2O=NH4OH,②氢氧化铵与盐酸反应生成氯化铵和水,NH4OH+HCl=NH4Cl+H2O,由①②可知答案为:NH3+HCl=NH4Cl.

(3)①A.Cu和稀盐酸不反应,锥形瓶与烧瓶内压强相等,不能形成喷泉,故不选;B与C.两物质都能反应,但不产生气体,容器内的压强没有变化,不能形成喷泉,故不选;D.Zn和稀硫酸反应,产生氢气,使锥形瓶内压强大于烧瓶内压强,形成喷泉,故选:D.

②酒精沸点是78.4℃,硫酸铜或硫酸钾溶于冷水后,溶液温度基本不变,不能使酒精汽化,锥形瓶内压强与烧瓶内压强是相等的,不会形成喷泉,故不选BD;生石灰与水反应放出大量的热量,浓硫酸溶解于水放出大量热量,会使液体的温度升高,达到酒精沸点而汽化,锥形瓶内压强会增大,大于烧瓶内压强时,就会形成喷泉,故选:AC.

阅读理解

I felt very sad not to be able to get the ticket for the film Titantic last Friday. I learned in the newspaper that ticket could be bought at the cinema box office (售票处) in Richland Hill every day between 10:00 and 4:00. Because I work from 9:00 to 5:30, the only time I could go to the cinema was during my 45-minute lunch time. It is a pity that the cinema is on the other side of the town, and the bus service between my office and Richland Hills is not very good. But if you are lucky, you can make the round(往返) trip in 45 minute.

Last Monday I stood at the bus stop for fifteen minutes, waiting for a bus. By the time I saw one come around the corner, there was not enough time left to make the trip---- so I had to go back to the office. The same thing happened on Wednesday. On Thursday my luck changed, I got on a bus right away and arrived at the cinema in twenty minutes. But when I got there, I found a long line of people at the box office. I heard one man say he had been waiting in line for fifty-five minutes. I found that I would not have enough time to wait in line, I caught the next bus and went back across the town.

By Friday I understood my only hope was to make the trip by car.it was not cheap,but I felt it would be worth ot to see the film. The trip by car only took 10 minutes, but it felt like one hour to me. When I reached the cinema, I was delighted to see that nobody was waiting in line. But quickly found out that it was because they had already sold all the tickets.

小题1: It seems that the writer of the story works     .

A.in a small town

B.in Richland Hills

C.on a farm near the town

D.at a bus service Center小题2: He tried to go to the cinema bo buy a ticket but really got there     .

A.five times

B.four times

C.three times

D.twice小题3:The underlined word “delighted” means     .

A.sure

B.sorry

C.surprised

D.pleased小题4: Which of the following is true according to the story?

A.The writer was too busy to have time for a rest during the day.

B.The buses running between his office and Richland Hills were always on time on Thursday.

C.He could buy the tickets neither before nor after work hours.

D.It always took him about twenty minutes to get to the cinema by bus.小题5:What’s the title of the story?

A.How to Get a Ticket

B.Tickets Sold out

C.A Wonderful Film

D.The Way to the Cinema

单项选择题