问题 选择题

化学知识中有很多的“相等”。请你判断下列说法中不正确的是

A.溶液稀释前后,溶质的质量相等

B.化合物中,元素正化合价数值等于负化合价数值

C.50g水和50g酒精混合,所得溶液的质量等于100g

D.50mL的水和50mL的酒精混合,所得溶液的体积等于100mL

答案

答案:D

A、溶液稀释前后,溶质的质量相等,正确,不符合题意;

B、在化合物中,正负化合价的代数和为零,元素正化合价数值等于负化和价数值,正确,不符合题意;

C、分子之间有间隔,所以50mL的水和50mL的酒精混合,所得溶液的体积应小于100mL,故错误,符合题意;

D、50g水和50g酒精混合,所得溶液的质量是100g,正确,不符合题意;

故选C.

完形填空

阅读表达(共5小题;每小题3分,满分15分)

阅读下面短文,并根据短文后的要求答题(请注意问题后的字数要求)。

Work is a very important part of life in the United States. When the early Protestant immigrants(新教徒移民) came to this country, they brought the idea that work was the way to God and heaven. This attitude, the Protestant Work Ethic(道德规范), still influences America today. Work is not only important for economic benefits, the salary, but also for social and psychological need, the feeling of doing something for the good of the society. Americans spend most of their lives working, being productive. For most Americans, their work defines them: they are what they do. What happens then, when a person can no longer work? Almost all Americans stop working at age sixty-five or seventy and retire. Because work is such an important part of life in this culture, retirement can be very difficult. Retirees often feel that they are useless and unproductive. Of course, _______________; but leaving one’s job, whatever it is, is a difficult change, even for those who look forward to retiring. Many retirees do not know how to use their time or they feel lost without their jobs.

Retirements can also bring financial problems. Many people rely on Social Security checks every month. During their working years, employees contribute a certain percentage of their salaries to the government. Each employer also gives a certain percentage to the government. When people retire, they receive this money as income. These checks do not provide enough money to live on, however, because prices are increasing very rapidly. Senior citizens, those over sixty-five, have to have savings in the bank or other retirement plans to make ends meet. The rate of inflation(通货膨胀) is forcing prices higher each year. Social Security checks alone cannot cover these growing expenses. The government offers some assistance, Medicare and welfare, but many senior citizens have to change their life styles after retirement. They have top spend carefully to be sure that they can afford to buy food, fuel and other necessities.

American society is only beginning to be concerned about the special physical and emotional needs of its senior citizens. The government is taking steps to ease the problem of limited income. They are building new housing, offering discounts in stores and museums and on buses, and providing other services such as free courses, food service, and help with housework.

76.What’s the general idea of this passage? (Please answer within 10 words.)

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77.Translate the underlined sentence in the first paragraph into Chinese.

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78.Please fill in the blank with proper words or phrases. (Please answer within 10 words.)

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79.Which sentence in the passage is the closet in meaning to the following sentence?

Retirees will have many economic difficulties after retiring.

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80.What other suggestions would you give to the government to take steps to ease the problems of limited income of the senior citizens? (Please answer within 30 words.)

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问答题 简答题