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标题: 求 prep1-1 谢谢！！！ [打印本页]

作者: saya630 时间: 2010-11-26 16:09
标题: 求 prep1-1 谢谢！！！

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.

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

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

麻烦帮我解释一下~ 题目意思谢谢！

作者: sdcar2010 时间: 2010-11-26 20:53
D is the answer.

1) Scientist synthesized a chemical called fullerenes.
2) Naturally occurring fullerenes were found in the mineral shungite.
3) Assumption: If same structure, then the chemical requires the same conditions to form
4) Conclusion: The condition on earth when the mineral shungite was formed could be known.

Answer D says the structures for fullerenes and the mineral shungite are different. Hence, the assumption is wrong. So is the conclusion then.

作者: saya630 时间: 2010-11-27 20:38
明白了谢谢！

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