问题 实验题

为了探究Cl2、SO2同时通入H2O中发生的反应,某校化学兴趣小组同学设计了如图所示的实验装置。

(1)气体发生装置A产生的气体是_____________。

(2)为验证通入D装置中的气体是Cl2过量还是SO2过量,某小组同学准备了以下试剂:①氯化铁溶液;②氯化亚铁溶液;③硫氰化钾溶液;④苯酚溶液;⑤品红溶液; ⑥酸性高锰酸钾溶液

Ⅰ.若Cl2过量:取适量D中溶液滴加至盛有__________(选填一个序号)的试管内,再加入____________(选填一个序号)试剂,实验现象是:                       

Ⅱ.若SO2过量:取适量D中溶液滴加至盛有____________(选填一个序号)的试管内,实验现象是:__________________________________。

(3)另一小组设计如图所示的装置图(图中夹持和加热装置略去),分别研究SO2和Cl2的性质。

①若从左端分别通入SO2和Cl2,装置A中观察到的现象是否相同?____________(填“相同”或“不相同”);

②若装置B中装有5.0 mL 1.0 mol·L-1碘水,当通入足量Cl2完全反应后,共转移了5.0×10-2 mol电子,该反应的化学方程式为                         

答案

(1)SO2       

(2)Ⅰ.②   ③(或④)   溶液呈红色(或紫色)  Ⅱ.⑥  溶液变成无色

(3)①相同    ②  5Cl2+I2+6H2O=2HIO3+10HCl

题目分析:(1)SO2易溶于水且与水能反应,所以通入水中溶液发生倒吸,F装置可以防倒吸,所以装置B为制取SO2的装置。

(2)Ⅰ.若Cl2过量,取适量D中溶液滴加至盛有氯化亚铁溶液试剂的试管内,Cl2可把Fe2+氧化为Fe3+,再加入硫氰化钾溶液会变血红色,或再加入苯酚溶液会变为紫色,根据溶液颜色的变化可证明氯气氧氧化亚铁离子过量。

Ⅱ.若SO2过量,取适量D中溶液滴加至盛有品红溶液的试管中,红色褪去,加热又恢复红色,证明含有二氧化硫。

(3)①二氧化硫能和有色物质反应生成无色物质,具有漂白性,氯气和水反应生成次氯酸,次氯酸具有强氧化性,能使有色物质褪色,所以若从左端分别通入SO2和Cl2,装置A中观察到的现象相同,都使品红褪色。

②装置B中装有5.0 mL 1.0 mol·L-1碘水,当通入足量Cl2完全反应后,共转移了5.0×10-2 mol电子,I2的物质的量为5.0×10-3 mol,说明I元素的化合价从o升高至+5价,被Cl2转化为HIO3,所以反应的化学方程式为:5Cl2+I2+6H2O=2HIO3+10HCl。

单项选择题
阅读理解

At 21,Ricardo Semler became boss of his father's business in Brazil,Semco,which sold parts for ships. Semler Junior worked like a mad man,from 7:30 am,until midnight every day. One afternoon,while touring a factory in New York,he broke down. The doctor who treated him said,"There's nothing wrong with you. But if you continue like this, you'll find a new home in our hospital. "Semler got the message. He changed the way he worked. In fact,he changed the ways his employees worked too.

He let his workers take more responsibility so that they would be the ones worrying when things went wrong. He allowed them to set their own salaries,and he cut all the jobs he thought were unnecessary,like receptionists and secretaries. This saved money and brought more equality(平等)to the company. "Everyone at Semco,even top managers,meets guests in reception,does the photocopying,sends faxes,types letters and dials the phone."

He completely reorganized the office:instead of walls,they have plants at Semco,so bosses can't shut themselves away from everyone else. And the workers are free to decorate their workspace as they want. As for uniforms,some people wear suits and others wear T-shirts.

Semco has flexible (灵活的)working hours:the employees decide when they need to arrive at work. Also,Semco lets its workers use the company's machines for their own projects,and makes them take holidays for at least thirty days a year.

It sounds perfect,but does it work? The answer is in the numbers:in the last six years,Semco's revenues (收入)have gone from $35 million to $212 million. The company has grown from eight hundred employees to 3,000. Why?

Semler says it's because of "peer pressure". Peer pressure makes employees work hard for everyone else. If someone isn't doing his job well,the other workers will not allow the situation to continue. In other words,Ricardo Semler treats his workers like adults rather than children, and expects them to act like responsible adults. And they do.

小题1:Why did Semler change the way he and his employees worked?

A.Because he went crazy because of overwork.

B.Because he had to receive treatment in hospital.

C.Because his father asked him to.

D.Because the doctor warned him of the danger of overwork.小题2:Semler made a variety of changes in his company Except that__________.

A.the number of the employees is reduced to save money

B.the employees can take only 30 days off for holiday every year.

C.flexible working hours were introduced

D.the employees enjoyed a lot of freedom小题3:What’s the main idea of Paragraph five?

A.Ricardo Semler’s new management method succeeded.

B.Ricardo Semler’s idea sounded perfect but not practical.

C.The company earned a lot of money.

D.The reason for his success.小题4:In his company, what does Ricardo Semler value most?

A.freedom

B.rules

C.responsibility

D.hard work