试题与答案

复方冬青油软膏具有强力迅速镇痛作用,其有效成分的分子模型如下图。下列说法中不正确

题型:选择题

题目:

复方冬青油软膏具有强力迅速镇痛作用,其有效成分的分子模型如下图。下列说法中不正确的是

 

A.该物质的化学式为C8H8O3

B.该物质分子中氢、氧原子的个数比为8:8∶3

C.该物质完全燃烧生成二氧化碳和水

D.该物质中含氧元素的质量分数最小

答案:

答案:D

题目分析:由图知,该物质的化学式为C8H8O3;该物质分子中氢、氧原子的个数比为8:8∶3,该物质由碳、氢、氧三种元素组成所以完全燃烧生成二氧化碳和水,该物质的一个分子中,各种原子总相对原子质量中氢原子最小,为8,所以氢原子所占比重最小,也就是氢原子的质量分数最小,也可以把每个元素的质量分数挨个算出来。

点评:化学式的意义分为宏观和微观,考试时经常以此为考察点,要熟悉其意义

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题型:完形填空

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小题1:A. to                B. /                C. at      

小题2: A. was going          B. go              C. went     

小题3: A. quietly             B. slowly           C. quickly   

小题4:A. of               B. to               C. about 

小题5: A. nothing            B. something         C. a sound

小题6:A. shouted            B. told              C. talked  

小题7:A. listen to            B. listen            C. hear  

小题8: A. like               B. liked            C. liking

小题9:A. go                B. to go            C. am going to

小题10: A. locked             B. closed           C. opened

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