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2004 National Chemistry Olympiad
50
2004 USNCO Problem 50: Valence Electrons
2004 USNCO Problem 50: Valence Electrons
Source:
July 22, 2013
Problem Statement
How many valence electrons are in the pyrophosphate ion, \ce{P2O7}^{4-}?
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48
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52
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54
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56
<span class='latex-bold'>(A) </span> 48\qquad<span class='latex-bold'>(B) </span> 52\qquad<span class='latex-bold'>(C) </span> 54\qquad<span class='latex-bold'>(D) </span> 56\qquad
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48
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52
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54
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56
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