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Contests
National and Regional Contests
USA Contests
USA Physics and Chemistry Contests
National Chemistry Olympiad
2007 National Chemistry Olympiad
2007 National Chemistry Olympiad
Part of
National Chemistry Olympiad
Subcontests
(2)
42
1
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2007 USNCO Problem 42
The mass of metal deposited by the electrolysis of an aqueous solution of metal ions increases in direct proportion to which property?
I. electrolysis current
\text{I. electrolysis current}
I. electrolysis current
II. electrolysis time
\text{II. electrolysis time}
II. electrolysis time
III. metal ion charge
\text{III. metal ion charge}
III. metal ion charge
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I only
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III only
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I and II only
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I, II, and III
<span class='latex-bold'>(A)</span>\ \text{I only} \qquad<span class='latex-bold'>(B)</span>\ \text{III only} \qquad<span class='latex-bold'>(C)</span>\ \text{I and II only} \qquad<span class='latex-bold'>(D)</span>\ \text{I, II, and III}\qquad
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III only
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I and II only
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I, II, and III
56
1
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2007 USNCO Problem 56
How many different compounds have the formula
C
3
H
8
O
\text{C}_3\text{H}_8\text{O}
C
3
H
8
O
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<span class='latex-bold'>(A)</span>\ \text{one} \qquad<span class='latex-bold'>(B)</span>\ \text{two}\qquad<span class='latex-bold'>(C)</span>\ \text{three} \qquad<span class='latex-bold'>(D)</span>\ \text{four} \qquad
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four