Question

10. Arrange the following compounds in a vertical list from highest boiling point (top) to lowest boiling point (bottom) and explain your answer on the basis of whether the substance is Polar, Nonpolar, Ionic, Metallic or Hydrogen bonding: O2, KF, NH3, Cu, HBr (Please note in this question you are not being asked to list BPs but the compounds in a list from highest to lowest BP on the basis of the type of compound.)

Answer 1

Cu Metallic

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KF Ionic   Metal - non metal bonding Hence ionic

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NH3,          Nonmetal-nonmetal - Hence Covalent

                There is difference in electronegativity of the elements Hence Polar

               N is a strongly elecronegative element with a lone pair of electros Hence NH3 can form H-bond

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HBr          Nonmetal-nonmetal -Covalent

                There is difference in electronegativity of the elements Hence Polar

                Br is not sufficiently electronegative for HBr to form H-bonds

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O2,, Homonuclear diatomic molecule. Hence Nonpolar

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N is more electronegative than Br.Therefore NH3 is more polar than HBr