试题与答案

食用含有“瘦肉精”(化学式为C12H18Cl2N2O)的肉对人体会产生危害,下列

题型:选择题

题目:

食用含有“瘦肉精”(化学式为C12H18Cl2N2O)的肉对人体会产生危害,下列对“瘦肉精”的认识不正确的是(  )

A.“瘦肉精”由碳、氢、氧、氮、氯五种元素组成

B.“瘦肉精”属于有机化合物

C.每个“瘦肉精”分子中含有35个原子

D.“瘦肉精”分子中碳、氢、氯、氮、氧的质量比为12:18:2:2:1

答案:

A、根据瘦肉精化学式C12H18Cl2N2O进行分析其由碳、氢、氧、氮、氯五种元素组成;故A说法正确;

B、根据含有碳元素的化合物叫有机化合物,简称有机物.碳的氧化物、碳酸盐、碳酸虽含碳,但其性质与无机物类似,因此把它们看作无机物.进行判断可知:瘦肉精属于有机化合物;故B说法正确;

C、根据标在元素符号右下角的数字表示一个分子中所含原子的个数;可知每个“瘦肉精”分子中含有

12+18+2+2+1=35个原子;故C说法正确;

D、根据化合物中各元素质量比=各元素的相对原子质量×原子个数之比,可得瘦肉精”分子中碳、氢、氯、氮、氧的质量比为(12×12):18:(35.5×2):(14×2):16,而12:18:2:2:1为瘦肉精”分子中碳、氢、氯、氮、氧的原子的个数比;故D说法错误;

故选D.

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题型:阅读理解

One summer vacation in my college, my roommate Ted asked to me to work on his father’s farm in Argentina. The idea was exciting. Then I had second thoughts. I had never been far from New England, and I had been homesick my first few weeks at college. What about the language? The more I thought about it, the more the idea worried me.

Finally, I turned down the invitation. Then I realized I had turned down something I wanted to do because I was scared and felt depressed(沮丧). That experience taught me a valuable lesson and I developed a rule for myself: do what makes you anxious(焦虑); don’t do what makes you depressed.

In my senior year, I wanted to be a writer. But my professor wanted me to teach. I hesitated. The idea of writing was much scarier than spending a summer in Argentina. Back and forth I went, making my decision, unmaking it. Suddenly I realized that every time I gave up the idea of writing, that downhearted feeling went through me.

Giving up writing really depressed me. Then I learned another lesson. To avoid the depression meant having to bear much worry and concern.

When I first began writing articles, I often interviewed big names. Before each interview I would get butterflies in the stomach. One of them was the great composer Duke Ellington. On the stage and on television, he seemed very confident. Then I learned Ellington still got stage fright(害怕). If Ellington still had anxiety attacks, how could I avoid them? I went on doing those frightening interviews. Little by little, I was even looking forward to the interviews. Where were those butterflies?

In truth, they were still there, but fewer of them. I had learned from a process psychologists(心理学家) call “extinction”. If you put an individual in an anxious situation often, finally there isn’t anything to be worried about, which brings me to a conclusion: you’ll never get rid of anxiety by avoiding the things that caused it.

The point is that the new, the different, is definitely scary. But each time you try something, you learn, and as the learning piles up, the world opens to you.

小题1:We can infer from the passage that the author________. 

A.finds it difficult to make decision

B.has found out what causes anxiety

C.was encouraged by Duke Ellington’s stage fright

D.no longer feels anxious about new experiences小题2:What does the word “extinction” in Paragraph 6 means?

A.a person’s loss of confidence little by little

B.the natural development of a child’s abilities

C.the inborn ability to avoid anxious situations

D.the process of losing fear by keeping facing anxiety小题3:Which of the following opinions does the writer probably accept?

A.Anxiety can be a positive drive

B.Hesitation leads to depression.

C.Avoiding anxiety reduces depression.

D.Depression is a signal that one is growing up.小题4:What's the best title for the passage?

A.Confidence: Key to Success

B.Anxiety: Challenge by Another Name

C.Depression: A Psychological Appearance

D.Success: A Trip Through Anxiety and Depression

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题型:选择题

某山共分布三类原生森林。下图显示三类森林每年每平方米净增的有机物质干重(NPP与温度变化,降水量变化的关系。据此完成1—3题。

1、上图信息显示,三类森林中[ ]

A.②的NPP对温度的变化最不敏感

B.NPP与温度变化都成正相关

C.②的NPP对降水的变化最敏感

D.NPP对降水的变化都很敏感

2、三类森林分布的海拔自低至高依次是[ ]

A.③①②

B.③②①

C.①②③

D.①③②

3、若①为针阔叶混交林,则该山可能位于[ ]

A.河南省

B.吉林省

C.安徽省

D.福建省

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题型:单项选择题

There has been much speculation about the origin of baseball. In 1907 a special commission decided that the modern game was invented by Abner Doubleday in 1839. One hundred years later the National Baseball Museum was opened to honor Doubleday. Historians, however, disagree about the origin of baseball. Some say that baseball comes from bat-and-ball games of ancient times. It is a matter of record that in the 1700s English boys played a game they called "baseball". Americans have played a kind of baseball since about 1800. At first tile American game had different rules and different names in various parts of the country — "town ball". "rounders", or "one old cat". Youngsters today still play some of these simplified forms of the game.
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What was the first professional baseball team called

A.New York Knickerbockers.

B.Milwaukee Braves.

C.Cincinnati Red Stockings.

D.Brooklyn Dodgers.

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