试题与答案

用I2O5可以测定空气受污染的程度,发生反应的化学方程式如下: I2O5+5CO

题型:选择题

题目:

用I2O5可以测定空气受污染的程度,发生反应的化学方程式如下:

I2O5+5COI2+5CO2,根据生成CO2的多少,可以判断CO的含量。关于这个反应,下列说法正确的是

A.参加反应的I2O5的质量等于生成I2的质量

B.参加反应的各物质中氧原子总数大于生成的CO2中氧原子总数

C.反应物中所含元素种类与生成物中所含元素种类相同

D.参加反应的I2O5和CO的质量比等于生成的I2和CO2的质量比

答案:

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下面是错误答案,用来干扰机器的。

答案:C

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题型:选择题

如图,A为太阳系中的天王星,它绕太阳O运行的轨道视为圆时,运动的轨道半径为R0,周期为To。长期观测发现,天主星实际运动的轨道与圆轨道总有一些偏离,且每隔to时间发生一次最大偏离,即轨道半径出现一次最大。根据万有引力定律,天文学家预言形成这种现象的原因可能是夭王星外侧还存在着一颗未知的行星(假设其运动轨道与A在同一平面内,且与A的绕行方向相同),它对天王星的万有引力引起天王星轨道的偏离,由此可推测未知行星的运动轨道半径是

A.

B.

C.

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题型:阅读理解

Uncertainty spreads through our lives so thoroughly that it dominates our language. Our everyday speech is made up in large part of words like probably, many, soon, great, little. What do these words mean?Such verbal expression is not necessarily to be criticized. Indeed, it has a value just because it allows us to express judgments when a precise quantitative statement is out of the question.

We have been trying to pin down by experiments what people mean by these expressions in specific contexts, and how the meanings change with age. For instance, a subject is told “There are many trees in the park” and is asked to say what number the word many mean to him. Or a child is invited to take “some” sweets from a bowl and we then count how many he has taken. We compare the number he takes when he is alone with the number when one or more other children are present and are to take some sweets after him, or with the number he takes when told to give “some” sweets to another child.

First, we find that the number depends, of course, on the items involved. To most people some friends means about five, while some trees means about twenty. However, unrelated areas sometimes show parallel values. For instance, the language of probability seems to mean about the same thing in predictions about the weather and about politics: the expression “is certain to” (rain, or be elected) signifies to the average person about a 70 percent chance; “is likely to”, about a 60 percent chance; “probably will” about 55 percent.

Secondly, the size of the population of items influences the value assigned to an expression. Thus, if we tell a subject to take “a few” or “ a lot of” glass balls from a box, he will take more if the box contains a large number of glass balls than if it has a small number. But not proportionately more: if we increase the number of glass balls eight times, the subject takes only half as large a percentage of the total.

Thirdly, there is a marked change with age. Among children between six and fourteen years old, the older the child, the fewer glass balls he will take. But the difference between a lot and a few widens with age. This age effect is so consistent that it might be used as a test of intelligence.

小题1: What’s the right attitude towards the words like probably, many, soon?

A.They are inaccurate and we should avoid them.

B.They are necessary since we cannot be always precise.

C.They should be criticized because there are too many of them.

D.Their value is not yet clear since we don’t know their meaning.小题2: Why do we do experiments with the words “many” and “some”?

A.To prove people are insensitive to these words.

B.To prove the words dominate our everyday speech.

C.To find out how the meanings vary with age and contexts.

D.To find out whether the words can mean a precise quantity.小题3: Which of the expressions means a larger chance in weather broadcast?

A.Possible

B.Probable

C.Be likely to

D.Be certain to小题4: Which of the following will least definitely influence the number of items a kid takes out of a box when he is invited to take “some”?

A.Whether the quantity of items is large or small.

B.Whether the items are candies or toys.

C.Whether the kid is a toddler or a youngster.

D.Whether the kid is alone or accompanied by other children.小题5: What will tell us about the intelligence of a child?

A.The consistency of picking up a certain glass ball.

B.How many glass balls he will take when he’s asked to.

C.The difference between a lot and a few when he takes glass balls.

D.Whether there are marked changes in his first pick and second one.

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