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USA Physics and Chemistry Contests
National Chemistry Olympiad
2004 National Chemistry Olympiad
50
50
Part of
2004 National Chemistry Olympiad
Problems
(1)
2004 USNCO Problem 50: Valence Electrons
Source:
7/22/2013
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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<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