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问题 选择题

经测定，由C3H7OH和C6H12组成的混合物中氧的质量分数为8%，则此混合物中氢的质量分数为 (    )

A．78%

B．22%

C．14%

D．13%

答案

答案：C

题目分析：将C3H7OH拆分为C3H6·H2O，将C6H12视为(C3H6)2，则混合物可看作(C3H6)与H2O的混合。因为氧的质量分数为8%，氧只出现于水(H2O)中，所以H2O占9%，则(C3H6)占91%，因此碳元素的含量是，所以混合物中氢元素的含量是1－8%－78%＝14%，答案选C。

点评：该题是中等难度计算题的考查，侧重对学生灵活运用基础知识解决实际问题的能力的培养，有利于培养学生的逻辑推理能力和发散思维能力。该题的关键是学好思维转换，有利于培养学生的创新思维能力。

多项选择题

砂岩峰林峡谷景观的特点是( )。

A．造型生动

B．溶洞遍布

C．奇峰林立

D．沟岩纵横

E．植物茂密
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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.

16（）

A.irrespective

B.independent

C.regardless

D.implausible
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