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 seriouly undermines the argument?
A. cofirming that the shungit 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 amount of carbon, from which the fullerenes apparently formed
D. The natural occurring fullerenes are arranged in a previously unknown crystalline structure
E. shungite itself is formed only under distinctive conditions.
Why choose D? It seems to me that none of them are correct?
Would you please be so kind as to explain it to me?Thanks!
D is correct.
If the natural occurring fullerenes are arranged in a previously unknown crystalline structure,that means,such an structure has not been discovered or observed in either nature or the lab.In this case, this natural formed fullerenes must be totally different from the one that has been formed in the lab.
Oh,yes!I understand it now!
Thanks!!!
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