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标题: prep-1求助,二战了。。。。 [打印本页]

作者: sophialj    时间: 2010-9-7 22:25
标题: prep-1求助,二战了。。。。
1.    (24179-!-item-!-188;#058&000705)

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, 我选的c,哪位童鞋解释下呢?
作者: bdsjb116    时间: 2010-9-7 23:51
题目说虽然fullerences最早在实验室里发现,但后来在大自然中夜发现了。由于实验室里的fullerenes需要特定的温度和压强,所以可以假设通过检测大自然中发现的fullerences来判断当时地壳的状态。

可以发现结论中缺乏实验室发现的物质和大自然中的物质是否相同的描述,臆断这两者相同

C.在fullerenes发现的地方含有很多的碳= 无关选项 mineral shungite有碳不代表大自然中的fullerenes和实验室的有同样的关系
D.大自然中发现是不同的结构。说明和实验室里的不同,进而不能用实验室的理论来推测大自然中的物质。
作者: ningguoguo    时间: 2010-9-8 16:20
谢!收益溜过~
作者: Kate200815019    时间: 2010-9-19 15:26
谢了 讲得很清楚




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