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USA Physics and Chemistry Contests
National Chemistry Olympiad
2010 National Chemistry Olympiad
3
3
Part of
2010 National Chemistry Olympiad
Problems
(1)
2010 USNCO Local #3: Phenolphythalein in a solution
Source:
11/21/2012
When phenolphythalein is added to an aqueous solution containing one of the following solutes the solution turns pink. Which solute is present?
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A
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NaCl
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KC
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C
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LiBr
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D
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NH
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NO
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{ <span class='latex-bold'>(A)</span>\ \text{NaCl} \qquad<span class='latex-bold'>(B)</span>\ \text{KC}_2\text{H}_3\text{O}_2 \qquad<span class='latex-bold'>(C)</span>\ \text{LiBr} \qquad<span class='latex-bold'>(D)</span>\ \text{NH}_4\text{NO}_3 }
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A
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NaCl
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B
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KC
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H
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C
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LiBr
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D
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NH
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NO
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