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问题 选择题

下列说法中正确的是（　　）

A．液体在任何温度下都能蒸发，但凝固都是在一定温度下进行

B．液体沸腾时要吸热，但温度不变

C．压缩体积可以使气体在任何温度下液化

D．物质从固态变成气态要放热，从气态变成固态，要吸热

答案

A、蒸发在任何温度下，都能进行，晶体凝固时必须有一定的温度，但非晶体不需要．故A不正确．

B、液体沸腾时要吸热，但温度不变，吸收的热正好用来完成沸腾．故B正确．

C、在一定的温度下压缩体积才能使气体液化．故C不正确．

D、物质从固态变成气态是升华现象，吸热．从气态变成固态，是凝华，要放热．故D不正确．

故选B

计算题

某校化学研究性学习课题组的同学们为了测定某氢氧化钙样品中Ca （OH）2含量（含有的杂质为CaCO3），共做了3次实验，使一定质量的该试样分别与同一种盐酸反应，所得相关实验数据记录如下表：

（1）在第_____次实验中，反应容器内有白色固体剩余．

（2）求原试样中Ca （OH）2的质量分数？

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单项选择题

Starting with his review of Skinner’s Verbal Behavior, Noam Chomsky had led the psycholinguists who argue that man has developed an innate (天生的) capacity for dealing with the linguistic universals common to all languages. Experience and learning then provide only information about the (1) instances of those universal aspects of language which are needed to communicate with other people within a particular language (2) .

This linguistic approach (3) the view that language is built upon learned associations between words. What is learned is not strings of words per se (本身), but (4) rules that enable a speaker to (5) an infinite variety of novel sentences. (6) single words are learned as concepts: they do not stand in a one-to-one (7) with the particular thing signified, but (8) all members of a general class.

This view of the innate aspect of language learning is at first not readily (9) into existing psychological frameworks and (10) a challenge that has stimulated much thought and new research directions. Chomsky argues that a precondition for language development is the existence of certain principles "intrinsic (原有的) to the mind" that provide invariant structures (11) perceiving, learning and thinking. Language (12) all of these processes; thus its study (13) our theories of knowledge in general.

Basic to this model of language is the notion that a child’s learning of language is a kind of theory (14) . It’s thought to be accomplished (15) explicit instruction, (16) of intelligence level, at an early age when he is not capable of other complex (17) or motor achievements, and with relatively little reliable data to go on. (18) , the child constructs a theory of an ideal language which has broad (19) power. Chomsky argues that all children could not develop the same basic theory (20) it not for the innate existence of properties of mental organization which limit the possible properties of languages.

19（）

A.instinctive

B.addictive

C.tentative

D.predictive
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