问题 选择题

a、b、c三种短周期元素在元素周期表中的相对位置如图所示,a与b的质子数之和比c的质子数少1,以下说法错误的是   

A.a与c均存在同素异形体

B.原子半径由大到小的顺序为:c > a > b

C.b的氢化物的稳定性小于 c的氢化物的稳定性

D.c的单质可用于制造太阳能电池

答案

答案:C

假设a的质子数为X,根据题意,可列出等量关系,X+X+1=X+8-1,可得X=6,依次得出a为碳元素,b为N元素,c为si元素。

A选项正确,C有常见的同素异形体有石墨,金刚石等,而硅则有多晶硅和单晶硅等。

B选项正确,周期表从左往右,原子半径依次减小,从上往下,原子半径依次增大,由这个规律可推断c > a > b。

C选项错误,氢化物稳定性随元素非金属性增强而增强,由于b的非金属性强于a,a强于c,所以b的氢化物稳定性应该大于c的氢化物,答案选C。

D选项正确,硅常用于半导体材料中。

完形填空

You are a German living in Berlin. One day you’ re walk¬ing down the street, minding your own business, when sudden¬ly a stranger comes up with a smile on his face. After stopping you, he holds a small electronic device (装置) close to his face and speaks slowly into it, saying, in English," Can you tell me where I can buy some sauerkraut?" What should you do? (a) Run away; (b) Call the police; or (c) Listen closely for the device to say in German," Konnen Sie mir bitte sagen, welches sauerkraut haufen kann?"

The most proper answer would be (c) because the person in front of you is only a tourist trying to enjoy himself. The de¬vice is said to be the world’s first portable(便携的) translator — a hand-held microcomputer that at the same time translates one spoken language into another. The four-pound, battery-op¬erated product is called the Voice, and it is the invention of Advanced Products and Technologies, an American electronics company. When the Voice is introduced in the Unite States in late April — at a price of (1,500 — it will be used to trans¬late spoken English into Italian, German, French and Span¬ish. The product comes with separate cartridges(盒式存储器) for each of the four languages, which can be changed when the user travels from one country to another. It will be sold in Eu¬rope soon after the US introduction, with cartridges that trans¬late Italian, German, French and Spanish into English.

The Voice uses a microchip(微型集成电路片) to trans¬late languages. It is Started by voice command and produces voice output through a built-in speaker. When the user makes a statement or asks a question, the Voice immediately repeats what has been said in another language.

1. The device held by the stranger is probably a kind of________.

A. a two-way radio                      B. language translator

C. easily-carried speaker                     D. a multi-functioned computer

2. What does the last sentence of the first paragraph mean?

A. Can you tell me where I can buy some sauerkraut?

B. Can I ask for some information from the police?

C. Would you like to try my device?

D. Would you not run away if I ask you where to buy some sauerkraut?

3. When the stranger says," Can you tell... sauerkraut?" he is ________.

A. learning German from his device

B. asking you the way to the sauerkraut shop

C. making fun of you with his device

D. testing his device for fun

4. Which of the following is not mentioned in the text?

A. The price of the hand-held microcomputer.

B. The function of the product Voice.

C. The producer pf the small electronic device.

D. The number of the device sold to the European coun¬tries.

填空题