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2013 National Chemistry Olympiad
3
2013 USNCO Problem 3: Mass of compound
2013 USNCO Problem 3: Mass of compound
Source:
May 23, 2013
Problem Statement
What mass of the compound \ce{CrO3}
(M = 100.0)
\text{(M = 100.0)}
(M = 100.0)
contains
4.5
×
1
0
23
4.5\times10^{23}
4.5
×
1
0
23
oxygen atoms?
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A
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2.25 g
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12.0 g
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C
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25.0 g
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D
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75.0 g
<span class='latex-bold'>(A) </span>\text{2.25 g}\qquad<span class='latex-bold'>(B) </span>\text{12.0 g}\qquad<span class='latex-bold'>(C) </span>\text{25.0 g}\qquad<span class='latex-bold'>(D) </span>\text{75.0 g}\qquad
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2.25 g
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B
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12.0 g
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25.0 g
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75.0 g
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