题目内容

【题目】A、B、C、D、E五种元素的原子序数依次递增,且均属于短周期元素,已知A是非金属元素,其电子层数与最外层电子数相等。Bn+和Cn+1与氖原子具有相同的电子层结构,且C是两性元素。Dn-、En-1与氩原子具有相同的电子层结构。

1写出这五种元素的元素符号

A.__________;B.__________;C.__________;D.__________;E.__________。

2写出E单质与NaOH溶液反应的化学方程式:____________________。

3比较A、B、C、D、E的半径大小_____________________。

【答案】1H Mg Al S Cl

2Cl2+2NaOH===NaCl+NaClO+H2O

3rA<rE<rD<rC<rB

【解析】短周期元素中电子层数与最外层电子数相等的有H、Be、Al。其中H为非金属元素,所以A为H。由于C为两性元素,则Bn+、Cn+1分别为Mg2+、Al3+。由于n=2,则Dn-、En-1分别为S2-、Cl。因此A、B、C、D、E分别为H、Mg、Al、S、Cl。A元素原子半径最小,B、C、D、E同周期,序数增大,其半径减小。

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【题目】 (共5小题;每小题2分,满分10分)

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

The need for love is deeply rooted in the human psyche(灵魂). 16 Separateness, according to psychologists, means to be cut off, helpless and alone in the world. It is the source of all anxiety.

17 It can be selfish and possessive, or unselfish and giving. Abraham Maslow distinguishes between two kinds of love: B-love or being love means love for another person; unselfish love not dependent upon your own needs. D-love or deficiency-love is a selfish possessive love which is based upon someone elses ability to satisfy your needs.

D-love is conditional. It depends upon whether personal needs continue to be met. But B-love is unconditional. 18 Furthermore, as it depends upon who you are, it is possible only when you allow yourself to be known to the other person.

The psychologist Erich Fromm also distinguished between two types of love. 19 Symbiotic union is an immature love based upon the satisfaction of needs and is similar to Maslows concept of D-love.

Mature love, on the other hand, is a relationship that allows individuals to retain (保持) their independence, their identity, and their integrity. In mature love people can overcome their sense of separateness yet continue to be themselves. The immature lover would say, I love you because I need you, but the mature one: ____20____

A. Every one of us needs love.

B. There are two types of love.

C. I need you because I love you.

D. Love is a way of overcoming the feeling.

E. It depends not upon what you do, but who you are.

F. These two types are quite different from each other.

G. They are immature love, called by him symbiotic union(共同体), and mature love.

【题目】根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

Are you concerned about the effect of the haze(雾霾) in Singapore on the health of your children? Then you should read the following passage.

"Young children, especially those with lung or heart illness, should avoid outdoor activity at PSI(Pollution Standards Index used in Singapore) levels above 100," says Dr Biju Thomas.

The immune system(免疫系统) of children is not mature. 16 Exposure to the haze can result in symptoms such as a blocked nose, dry throat, breathing difficulty, and so on.

Children who are exposed to the haze and experience any of these symptoms which are not serious should recover on their own in time if they limit their exposure to the haze. 17

To keep children safe during the haze in Singapore, parents should keep doors and windows closed at home. Ensure children drink plenty of pure water every day.

18 The answer is that there arent any N95 masks designed for use by children. Thats because these masks are made to create a seal(密封) around the mouth and nose of the adult user so particles(颗粒) can not get in. 19 Surgical masks may not offer enough protection from the harmful particles in the haze, which is very small (2.5 microns or less). There is usually some gap between the surgical mask and the face, through which the haze particles may easily get in. 20 However, if it is necessary to take children outdoors during a haze, parents may wish to offer childrens surgical mask to their children, if it brings them comfort, such as filtering out the smell from the haze.

A. So during a haze, children are especially at risk.

B. Are N95 masks and surgical masks suitable for children?

C. The available N95 masks may not fit tightly on the face of a child.

D. Allow children to make regular travels from one building to another.

E. However, if the symptoms continue, they should ask a doctor for help.

F. So you can use a conditioner instead of opening the windows regularly.

G. So it is best to keep children indoors to protect them from the haze when the PSI is high.

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