已知有如下反应: ①2BrO3-+Cl2=Br2+2ClO3-, ②ClO3-+

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问题:

已知有如下反应:

①2BrO3-+Cl2=Br2+2ClO3,             ②ClO3-+5Cl+6H=3Cl2+3H2O,

③2FeCl3+2KI=2FeCl2+2KCl+I2,         ④2FeCl2+Cl2=2FeCl3

下列各微粒氧化能力由强到弱的顺序正确的是

A.ClO3->BrO3->Cl2>Fe3+>I2

B.BrO3->Cl2>ClO3->I2>Fe3+

C.BrO3->ClO3->Cl2>Fe3+>I2

D.BrO3->ClO3->Fe3+>Cl2>I2

考点:氧化性、还原性强弱的比较物质的推断
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下面的文字在标点符号、用词、语句等方面有四处错误,请找出来并加以修改。

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_______________________________________________。

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阅读理解

     One stormy night many years ago,an elderly man and his wife entered the hall of a small hotel in

 Philadelphia.Trying to get out of the rain,they came the front desk hoping to get some shelter for the night.

     "Could you possibly give us a room here?" the husband asked.

     The clerk,a friendly man with a winning smile,looked at the couple and explained that there were three

conventions in town."All of our rooms are taken," the clerk said."But I can't send a nice couple like you out into the rain at one o'clock in the morning.Would you perhaps be willing to sleep in my room?It's not

exactly a suite,but it will be good enough to make you folks comfortable for the night."

     When the couple declined,the young man pressed on."Don't worry about me;I'll make out just fine.

" the clerk told them.So the couple agreed.

     As he paid his bill the next morning,the elderly man said to the clerk,"You are the kind of manager who should be the boss of the best hotel in the United States.Maybe someday I'll build one for you." The

looked at them and smiled.The three of them had a good laugh.As they drove away,the elderly couple

agreed that the helpful clerk was indeed exceptional,as finding people who are both friendly and helpful

isn't easy.

     Two years passed.The clerk had almost forgotten the incident when he received a letter from the old

man.It recalled that stormy night and enclosed a roundtrip ticket to New York,asking the young man to

pay them a visit.

     The old man met him in New York,and led him to the corner of Fifth Avenue and 34th street.He then

pointed to a great new building there,a pale reddish stone,with turrets and watchtowers thrusting up to the sky."That," said the older man,"is the hotel I have just built for you to manage." "You must be joking," the

young man said."I can assure you I am not,"said the older man,a sly smile playing around his mouth.

     The older man's name was William Waldorf Astor,and that magnificent structure was the original

WaldorfAstoria Hotel.The young clerk who became its first manager was George C.Boldt.This young

clerk never foresaw the turn of events that would lead him to become the manager of one of the world's

most glamorous hotels.

1. The purpose of the following author writing this story is to________.

A. give people a good laugh

B. cover some facts

C. promote the business of WaldorfAstoria Hotel

D. deliver a lesson

2. Which of the following statements about the story is NOT true ?

A. The story took place at about one a.m..

B. The old couple was too poor to afford a luxurious room.

C. The clerk was willing to help those in need.

D. The clerk received an unexpected invitation from the old man.

3. The underlined word "conventions" in Para 3.can be replaced by________.

A. rooms    

B. suites

C. meetings    

D. hotels

4. Which of the following proverbs suits the story the best?

A. Every little thing helps.

B. Make hay while the sun shines.

C. Man proposes;God disposes (处理,决定).

D. One good turn deserves another.

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设A,B均为n阶可逆矩阵,且AB=B-1A-1,则r(E+AB)+r(E-AB)=______.

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在该环境电磁波强度下长期居住、工作和生活的一切人群(包括婴儿、孕妇和老弱病残者)可能引起潜在性不良反应的区域;在此区内可建造工厂和机关,但不许建造居民住宅、学校、医院和疗养院等,已建造的必须采取适当的防护措施。

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大量服用维生素C,可使尿液呈()。

A、酸性

B、碱性

C、中性

D、弱碱性

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