问题 填空题

乙炔是有机合成工业的一种原料,工业上曾用CaC2与水反应制备乙炔。

(1)CaC2中C22-与O22+互为等电子体,O22+的电子式可表示为       ;1 mol O中含有的π键数目为       

(2)将乙炔通入[Cu(NH3)2]Cl溶液生成Cu2C2,红棕色沉淀。Cu基态核外电子排布式为       

(3)乙炔与氢氰酸反应可得丙烯腈(H2C=CH—C≡N)。丙烯腈分子中碳原子轨道杂化类型是       ;分子中处于同一直线上的原子数目最多为       

(4)CaC2晶体的晶胞结构与NaCl晶体的相似(如右图所示),但CaC2晶体中哑铃形C22-的存在,使晶胞沿一个方向拉长,CaC2晶体中1个Ca2周围距离最近的C22-数目为       

答案

(1)[∶O⋮⋮O∶]22NA

(2)[Ar]3d10(或1s22s22p63s23p63d10)

(3)sp2和sp 3

(4)4

由C22-电子式为[∶C⋮⋮C∶]2可推知O22+电子式为[∶O⋮⋮O∶]2,1 mol O22+中含有π键数目为2NA,氧氧三键中含两个π键。Cu由Cu原子失去1个电子而得到,故基态核外电子排布式为1s22s22p63s23p63d10。丙烯腈分子中碳碳双键为sp2杂化,—C≡N键为sp杂化,其分子中有一个三键,故共键的原子为≡N即3个原子共线。

(4)由晶体结构可知CaC2晶体中1个Ca2周围距离最近的C22-数目不是6个而是4个,因为哑铃形C22-只向一个方向拉长,此方向上的两个C22-与Ca2距离不是最近,所以最近且等距的有4个。

阅读理解

阅读理解

     When you do some minor image editing (修正) on your computer screen, you may make some

mistakes, so from time to time you'd click undo (撤消).

     There are things in life we cannot undo as easily and completely as we would with our computer

files. A wrong turn, a hurtful word said to a loved one, a bad move - these we all commit as we walk

our life's journeys, no matter how careful we are in our steps. Once committed, we can no longer undo

many of these mistakes, especially because unlike with our computer documents, each thing we do and

say has vast impact as they involve not just us - the file that we are working on - but also others, the

unopened files and computer programs in our system.

     So I guess our life's mistakes are not like our pencil scrawls (潦草书写) that can be effectively

corrected with an eraser, or errors on our computer works that can be undone with an undo button.

But there are effective and reliable tools we can use-APOLOGY and FORGIVENESS. Simply click

the APOLOGY button when you have committed a mistake that has hurt a loved one and the words

"I'm Sorry" will flash on the other person's screen. But, you have to be truly sorry and you must be

prepared not to commit the same mistake again for your APOLOGY to work. Sincerity is definitely a

necessary part.

     When someone clicks the APOLOGY button and the words "I'm sorry" flash on your screen, all

you have to do is click back the FORGIVENESS (原谅) button. It means that you have wholeheartedly

accepted the other person's APOLOGY. But not only that. You also have to click it when someone has

sent you back the message "It's okay. Forget about it.". It means that you are also forgiving yourself for

your mistake; that you won't keep feeling so bad having committed it.

      And lastly, don't forget to keep clicking the SAVE button. Going through the whole process of

editing-of doing and undoing, of apologizing and forgiving - is useless if you fail to save the LESSON for

future use. Let the saved file be a reminder of the healing process you once went through to make

yourself better; for you not to forget the lesson; and for others to access and learn from.

1. Which of the following is TRUE?

A. However careful we are, we still make mistakes in life.

B. Things we do and say can affect computer programs in our system.

C. We can undo life's mistakes if we are careful enough.

D. An eraser is an effective tool for our computer works.

2. The APOLOGY button should be clicked when ________.

A. one wants to make the computer work perfectly

B. one's mistakes won't influence others any more

C. one is actually saying "I'm sorry"

D. one won't make the same mistake again

3. What does the underlined word "it" in Paragraph 4 refer to?

A. The UNDO button.

B. The APOLOGY button.

C. The SAVE button.

D. The FORGIVENESS button.

4. We need to click the SAVE button in life because ________.

A. we want to go through the whole process of editing

B. we need to learn a lesson from the past mistakes

C. we want to make the healing process faster

D. we need to use the computer properly

问答题 简答题