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USA Physics and Chemistry Contests
National Chemistry Olympiad
2010 National Chemistry Olympiad
14
14
Part of
2010 National Chemistry Olympiad
Problems
(1)
2010 USNCO Local #14: Family of Elements
Source:
11/21/2012
Which family of elements has solid, liquid, and gaseous members at
2
5
∘
C
25^{\circ} \text{C}
2
5
∘
C
and
1
atm
1 \text{atm}
1
atm
pressure?
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alkali metals (Li-Cs)
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pnictogens (N-Bi)
<span class='latex-bold'>(A)</span>\hspace{.05in}\text{alkali metals (Li-Cs)} \qquad<span class='latex-bold'>(B)</span>\hspace{.05in}\text{pnictogens (N-Bi)} \qquad
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alkali metals (Li-Cs)
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pnictogens (N-Bi)
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C
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chalcogens (O-Te)
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D
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halogens (F-I)
<span class='latex-bold'>(C)</span>\hspace{.05in}\text{chalcogens (O-Te)} \qquad<span class='latex-bold'>(D)</span>\hspace{.05in}\text{halogens (F-I)}\qquad
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chalcogens (O-Te)
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halogens (F-I)