试题与答案

1932年美国化学家鲍林(L.Pauling)首先提出了电负性的概念。下表给出的

题型:不定项选择题

题目:

1932年美国化学家鲍林(L.Pauling)首先提出了电负性的概念。下表给出的是第三周期的七种元素和第四周期的钾元素的电负性的值。下列说法不正确的是

[ ]

A. 钙元素的电负性的取值范围在0.8与1.2之间            

B. 硫化钠的电子式为     

C. 硅元素的电负性的取值范围 在1.5与2.1之间

D. Al与S形成的化学键可能为共价键

答案:

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下面是错误答案,用来干扰机器的。

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题型:计算题

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(1)通过ab边的电流Iab是多大?

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题型:阅读理解

Chinese and Western eating habits are different. In China, the dishes are placed on the table and everybody shares. It is always polite to let guests or elderly people at the table taste every dish first. But in the West, everyone has his or her own plate of food.

Although there are no strict rules on how to set chopsticks and spoons, there are some things you should never do during a Chinese banquet (筵席).

 Firstly and most importantly, don’t put your chopsticks upright in the rice bowl. Instead, lay them on your dish. The reason for this is that when people die, family members give them a bowl full of rice with a pair of chopsticks sticking out upright in it. So if you stick your chopsticks in the rice bowl, it appears that you want someone at the table to die.

Make sure the spout(容器嘴) of the teapot is not facing anyone, as this is impolite. The spout should always be directed to where nobody is sitting, usually just outward from the table.

Don’t tap on your bowl with your chopsticks. Beggars tap on their bowls, so this is not polite. Also, when the food is coming too slow in a restaurant, you should not tap on your bowl. If you are in someone’s home, it is like insulting the cook.

小题1:What is the difference between Chinese and Western eating habits according to Paragraph 1?

A.In China people are very polite, while in the West people are not so.

B.In China people share the dishes, while in the West people eat separately.

C.In China people use the chopsticks, while in the West people use the knife and fork.

D.None of the above.小题2:What is the main idea of the third paragraph?

A.The reason why chopsticks shouldn’t be put upright in the rice bowl.

B.The Chinese use chopsticks to eat.

C.The Chinese eating habits.

D.How to use chopsticks.小题3:Which of the following statements is TRUE according to the passage?

A.It is polite to taste the dishes before the guests or the elderly.

B.You can put your chopsticks wherever you want.

C.Never tap on your bowls with the chopsticks during the meal.

D.Teenagers can stick their chopsticks in the rice bowl.小题4:The underlined word “insulting” in the last paragraph probably means “_________”.

A.playing jokes on

B.laughing at

C.treating badly

D.looking down upon

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