“黄铜”是铜锌合金，具有较机械性能，比纯铜耐腐蚀，街头许多“_爱下问搜题

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问题计算题

“黄铜”是铜锌合金，具有较机械性能，比纯铜耐腐蚀，街头许多“金色”饰品就是用它来制作的．现取20.0g某种黄铜投入154.7g某浓度的稀硫酸中，恰好完全反应后剩余的溶液和残余固体总质量为174.5g．请计算：

（1）产生氢气的质量为多少g？

（2）这种黄铜中铜的质量分数为多少？

（3）反应后溶液中溶质的质量分数是多少？

答案

（1）产生氢气的质量=20.0g+154.7g-174.5g=0.2g

（2）设锌的质量为x；生成的硫酸锌的质量为y

Zn+H₂SO₄=ZnSO₄+H₂↑

65 161 2

x y 0.2g

x=6.5g

铜的质量为：20.0g﹣6.5g=13.5g

黄铜中铜的质量分数为：100%=67.5%

（3）

y=16.1g

反应后溶液的质量为：174.5g﹣13.5g=161g

反应后溶液中溶质的质量分数为：×100%=10%

答：（1）产生氢气的质量为0.2g；（2）这种黄铜中铜的质量分数为67.5%；（3）反应后溶液中溶质的质量分数是10%．

填空题

A good translator is by definition bilingual. The opposite is not ______(1) true, however. A born and bred bilingual will still need two__________(2) to become a translator: first, the skills and experience necessary for__________(3); second, knowledge of the field in which he or she will__________(4). The skills and experience for translation include the ability to write ______(5) in the target language, the ability to read and understand the_________(6) language material thoroughly, and the ability to work with the latest__________(7) and communication hardware and software.Does a born and bred bilingual__________(8) a better translator than someone who learned language B later in__________(9) There is no definite answer, but the following issues are important.__________(10), a born and bred bilingual often suffers from not truly knowing __________(11) language well enough to translate, with some even suffering from what __________(12) known as a lingualism, a state in which a person lacks_________(13) full, fluent command of any language. Second, born and bred bilinguals__________(14) don’’t know the culture of the target language well enough to_________(15) top-quality translations, or cannot recognize what aspects of the source language__________(16) its culture need to be treated with particular care, as they_________(17) in a sense too close to the language. And last, they often_________(18) the analytical linguistic skills to work through a sticky text.On_________(19) other hand, the acquired bilingual may not have the same in-depth _________(20) of colloquialisms, slang, and dialect that the born bilingual has. Also, the acquired bilingual will not be able to translate as readily in both directions (from B to language A and A to language B). Finally, born bilinguals often have a greater appreciation of the subtleties and nuances of both their languages than someone who learns their B language later in life can ever hope to have.

问答题

请写出计算机的应用领域。