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National Chemistry Olympiad
2010 National Chemistry Olympiad
7
7
Part of
2010 National Chemistry Olympiad
Problems
(1)
2010 USNCO Local #7: Balancing an equation
Source:
11/21/2012
What is the coefficient for
O
2
\text{O}_2
O
2
when the following reaction
_
As
2
S
3
+
_
O
2
→
_
As
2
O
3
+
_
SO
2
\_\text{As}_2\text{S}_3+\_\text{O}_2 \rightarrow \_\text{As}_2\text{O}_3+\_\text{SO}_2
_
As
2
S
3
+
_
O
2
→
_
As
2
O
3
+
_
SO
2
is correctly balanced with the smallest integer coefficients?
<
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A
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5
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B
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6
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C
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8
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(
D
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9
<span class='latex-bold'>(A)</span> 5 \qquad<span class='latex-bold'>(B)</span> 6 \qquad<span class='latex-bold'>(C)</span> 8 \qquad<span class='latex-bold'>(D)</span> 9 \qquad
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(
A
)
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5
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(
B
)
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6
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>
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C
)
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8
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(
D
)
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9