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USA Physics and Chemistry Contests
National Chemistry Olympiad
2013 National Chemistry Olympiad
48
2013 USNCO Problem 48: Metalloids
2013 USNCO Problem 48: Metalloids
Source:
April 20, 2013
Problem Statement
In which set are both elements metalloids?
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A
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Cr and Mo
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B
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Ge and As
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C
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Sn and Pb
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D
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Se and Br
{ <span class='latex-bold'>(A)</span>\ \text{Cr and Mo}\qquad<span class='latex-bold'>(B)</span>\ \text{Ge and As}\qquad<span class='latex-bold'>(C)</span>\ \text{Sn and Pb}\qquad<span class='latex-bold'>(D)</span>}\ \text{Se and Br}\qquad
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A
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Cr and Mo
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B
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Ge and As
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C
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Sn and Pb
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D
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Se and Br
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