试题与答案

根据物质相对分子质量和所含元素化合价有规律排列的一组化学式:CH4、X、H2O、

题型:选择题

题目:

根据物质相对分子质量和所含元素化合价有规律排列的一组化学式:CH4、X、H2O、HF,其中X应选择(  )

A.HCl

B.H2S

C.PH3

D.NH3

答案:

CH4、H2O、HF它们的相对分子质量分别为:16、18、20,所以相对分子质量依次增大;

三种物质中均含有氢元素,另一种元素的化合价分别为-4、-2、-1,化合价依次增大;故X的相对分子质量应大于16,小于18;化合价应大于-4,小于-2.

A、HCl的相对分子质量为36.5,不符合题意;

B、H2S的相对分子质量为34,不符合题意;

C、PH3的相对分子质量为34,不符合题意;

D、NH3的相对分子质量为17,氮元素的化合价为-3;符合题意.

故选D.

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题型:阅读理解

根据短文内容,选择最佳答案。

Mrs. Green’s telephone number was three-four-six-three, and the number of the cinema near her house was three-four-six-four. So people often made a mistake and telephoned her when they wanted the cinema.

One evening the telephone rang and Mrs. Green answered it. A tired man said, “At what time your last film begin?”

“I’m sorry,” said Mrs. Green, “but you have the wrong number. This is not the cinema.” “Oh. It began twenty minutes ago,” said the man, “I am sorry about that. Goodbye.” Mrs. Green was very surprised, so she told her husband. He laughed and said, “The man’s wife wanted to go to the cinema, but he was feeling tired, so telephoned the cinema. The man’s wife heard him, but she didn’t hear you. Now they will stay at home this evening and the husband will be happy.”

小题1:Mrs. Green’s telephone number was ______.

A.3634

B.3463

C.4636

D.3464小题2:People often made a mistake and telephoned her when they wanted _____.

A.to sleep

B.the shop

C.the cinema

D.the visit小题3:When Mrs. Green answered the phone, who didn’t hear her ?.

A.Mr. Green

B.The man

C.The man’s wife.

D.Anybody.小题4:Why was Mrs. Green very surprised after she answered the telephone? Because    .

A.the man rang a wrong number

B.the man said sorry to her

C.the man didn’t answer her and said another thing

D.the man’s voice was very slow小题5:what will the man most probably do after the telephone?

A.stay at home.

B.go to the cinema.

C.go to Mr. Green’s.

D.go to work.

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