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（1）如图为有害物质甲醛（其水溶液即福尔马林）的结构示意图，该物质的化学式为______．

（2）中和一定质量、一定溶质的质量分数的稀硫酸，当用mg氢氧化钠时恰好完全反应，写出该反应的化学方程式______；若改用mg氢氧化钾时，反应后溶液中的溶质是______．

答案

（1）根据甲醛的结构示意图可知，每分子甲醛含有两个氢原子，一个碳原子，一个氧原子，所以化学式CH2O；

（2）稀硫酸和氢氧化钠中和反应化学方程式为：2NaOH+H2SO=Na2SO4+2H2O，

根据反应的化学方程式，mg氢氧化钠中和硫酸的质量

2NaOH+H2SO4═Na2SO4+2H2O

80 98

mg

98m
80
g

mg氢氧化钾中和硫酸的质量

2KOH+H2SO4═K2SO4+2H2O

112 98

mg

98m
112
g

由

98m
80
g＞
98m
112
g，

因此，用mg氢氧化钠中和一定质量和一定质量分数的稀硫酸，若改用mg的氢氧化钾时，硫酸会有剩余所得溶液中的溶质为：K2SO4、H2SO4

解答题
六年级二班的学生每人从家里带来一本课外书，办起小小图书室，共有连环画18本，故事书15本，科技书12本，其它书5本．把书的本数分别填写在下面的统计表里．
种类合计连环画故事书科技书其它
数量（本）
（1）______书最多，______书最少；
（2）连环画比科技书多______%；
（3）故事书是其它书的______倍；
（4）根据统计表制成扇形统计图．
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It is clear that we are rapidly becoming a global culture. New forms of information technology, intercontinental travel, and the complex nature of economics are all elements in such a change. Japan, an ancient (1) culture, now dominates the West economically while its own traditional (2) is rapidly becoming (3) in the process.
It does not take a great deal of analysis to see the vast interchanges of cultural influences in the world today. The thirst for (4) fashions, popular music, and the other elements of consumer culture (5) great inroads in non-Western lands while the West seeks out everything from the religious traditions of the Ease (6) the art and music these countries produce. In the field of (7) , to cite one conspicuous example, contemporary readers seek books (8) those of the West. Latin American authors, as well as those from Africa, Asia, and India, now find appreciative audiences.
A (9) culture does not mean a unitary or "one world" culture. It does mean that people are increasingly aware of the diversity of culture. World events enter our living rooms so that things that may once have been (10) of as distant (11) now greet us immediately and in color. We may watch those events on a television made in Japan while wearing clothes sewn in Thailand and shoes made in Hungary while snacking (12) food grown in Mexico. Such an economic interdependence reflects the reality of a global banking system, the globalization of the economy, and the increasing (13) of information and information technologies.
(14) has this shrinking of distances (and attitudes) become more clear than in the academic debates over what constitutes a liberal (15) education today. Is it possible (or desirable) to have the Western core of humanities (16) the center-piece of a curriculum The place of non-Western and non-traditional cultures as part of the general (17) of a student is hotly argued in educational circles. The very fact of that discussion (18) to the emergence of a global consciousness with a continued shrinking of parochial attitudes. The (19) that such globalization is hotly debated only emphasizes the profound nature of the (20) taking place in our culture.
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