问题 填空题

右图为持续电解含一定CaCl2的溶液的装置(以铂为电极),A为电流表。电解一段时间t1后,将CO2连续通入电解液中。

                

(1)电解时,F极发生     反应,电极反应式为       ,E极发生      反应,电极反应式为                ,电解总反应式为                   

(2)电解池中产生的现象:

                                              ;

                                              ;

                                              

答案

(1)氧化  2Cl--2e-Cl2↑ 还原  2H++2e-H2↑  2Cl-+2H2O2OH-+H2↑+Cl2

(2)①通电后E极处溶液呈红色

②通电时,E极、F极均有气体生成

③通CO2时,溶液中先出现白色沉淀,继续通CO2沉淀又消失

溶液中含有:Ca2+、H+、Cl-、OH-,通电时,Ca2+、H+移向阴极,由于H+放电能力比Ca2+强,在E极上发生反应:2H++2e-H2↑;Cl-、OH-移向阳极,Cl-在阳极放电;2Cl-+2e-Cl2↑,电解一段时间t1后,溶液中OH-浓度增大,通入CO2后会有CaCO3沉淀生成,继续通入CO2,则白色沉淀溶解。

阅读理解

Would you like to be a king or queen? To have people waiting on you hand and foot? Many Americans experience this royal treatment every day. How? By being customers. The American idea of customer service is to make each customer the center of attention. Need proof? Just listen to the commercials. Most of them sound like the McDonald’s ad: “We do it all for you.” Actually, not all stores in America roll out the red carpet for their customers. But wherever you go, good customer service means making customers feel special.

People going shopping in America can expect to be treated with respect from the very beginning. Most places don’t have a “furniture street” or a “computer road” which allow you to compare prices easily. Instead, people often “let their fingers do the walking” through the store hot lines. From the first “hello”, customers receive a satisfying response to their questions. This initial contact can help them decide where to shop.

When customers get to the store, they are treated as honored guests. Customers don’t usually find store clerks sitting around watching TV or playing cards. Instead, the clerks greet them warmly and offer to help them find what they want. In most stores, the clear signs that label each department make shopping a breeze. Customers usually don’t have to ask how much items cost, since prices are clearly marked. And unless they’re at a flea market or a yard sale, they don’t bother trying to bargain.

When customers are ready to check out, they find the nearest and shortest checkout lane. But as Murphy’s Law would have it, whichever lane they get in, all the other lanes will move faster. Good stores open new checkout lanes when the lanes get too long. Some even offer express lanes for customers with 10 items or less. After they pay for their purchases, customers receive a smile and a warm “thank you” from the clerk. Many stores even allow customers to take their shopping carts out to the parking lot. That way, they don’t have to carry heavy bags out to the car.

小题1: By quoting (引用) the McDonald’s ad: “We do it all for you”, the author intends to_______.

A.suggest that customers believe what commercials say deeply

B.show readers the American idea on good customer service

C.express all the stores pay much attention to the customers

D.persuade readers to choose the stores with ads correctly小题2:In the USA, what may you do at first if you want to do some shopping?

A.To visit a professional street with lots of similar stores.

B.To compare prices in many shops in the same street.

C.To make phone calls and get better shopping choices.

D.To receive other customers’ answers to the questions.小题3:The underlined words “a breeze” in Para.3 most probably means _________.

A.an easy job

B.a trouble  

C.a funny thing  

D.a boring task小题4:Which of the followings shows American stores offer convenience to customers in this passage?

A.The store clerks don’t usually sit around watching TV or playing cards.

B.Some stores offer price bargain to the customers like a yard sale.

C.The clerks give customers a smile and a warm “thank you” after paying.

D.Some stores open new checkout lanes when the lanes are crowded.小题5:Which of the following can be the best title of this passage?

A.Customer Service in America

B.Excellent Stores in America

C.Shopping Rules in America

D.Being King or Queen in America

单项选择题