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标题: 超难题,一点头绪都没有 [打印本页]

作者: sunandmoon    时间: 2008-3-29 18:51
标题: 超难题,一点头绪都没有

 

Although fullerenes--spherical molecules made entirely of carbon--were first found in the laboratory, they have since been found in nature, formed in fissures of the rare mineral shungite.  Since laboratory synthesis of fullerenes requires distinctive conditions of temperature and pressure, this discovery should give geologists a test case for evaluating hypotheses about the state of the Earth's crust at the time these naturally occurring fullerenes were formed.

 

Which of the following, if true, most seriously undermines the argument?

 

(A) Confirming that the shungite genuinely contained fullerenes took careful experimentation.

(B) Some fullerenes have also been found on the remains of a small meteorite that collided with a spacecraft.

(C) The mineral shungite itself contains large amounts of carbon, from which the fullerenes apparently formed.

(D) The naturally occurring fullerenes are arranged in a previously unknown crystalline structure.

(E) Shungite itself is formed only under distinctive conditions.

答案选D。完全不懂!希望牛人指点!


作者: pharmacystar    时间: 2008-3-29 19:58

这道题很偏,就是一道化学题,呵呵

fillerenes是一种分子,虽然第一次在实验室被发现,但是nature中早都存在了,

提干认为nature中自然形成的天然fillerenes和实验室合成的是同一种结构

D选项提出,天然的fillrenes按照从前不知道的晶体结构排列

因为lab先发现,天然的后发现,所以做lab实验时不可能合成和天然的一样的晶体结构,更加说明天然的和人工合成的不是同一种结构,所以lab的实验条件对推断自然界中的东西意义不大

btw 都叫 fillerenes是因为分子结构相同,但是分子要进一步组合成晶体,所以晶体结构不同,生成的条件就不同


作者: 一直在路上    时间: 2008-3-30 22:59

叹为观止..学习了!


作者: sunandmoon    时间: 2008-3-30 23:24

太强悍了!






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