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USA Physics and Chemistry Contests
National Chemistry Olympiad
2004 National Chemistry Olympiad
53
53
Part of
2004 National Chemistry Olympiad
Problems
(1)
2004 USNCO Problem 53: Boiling Points
Source:
7/22/2013
The boiling points of the halogens, \ce{F2}, \ce{Cl2}, \ce{Br2} and \ce{I2} increase in that order. This is best attributed to differences in
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covalent bond strengths
<span class='latex-bold'>(A) </span>\text{covalent bond strengths}\qquad
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covalent bond strengths
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dipole forces
<span class='latex-bold'>(B) </span>\text{dipole forces}\qquad
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dipole forces
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London dispersion forces
<span class='latex-bold'>(C) </span>\text{London dispersion forces}\qquad
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London dispersion forces
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colligative forces
<span class='latex-bold'>(D) </span>\text{colligative forces}\qquad
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colligative forces