Respuesta :
Answer:
(a) [tex]K_{2}S[/tex] (b) [tex]Br_{2}[/tex]
Explanation:
(a) [tex]K_{2}S[/tex] is an ionic compound in which [tex]K^{+}[/tex] and [tex]S^{2-}[/tex] ions are tightly bound together through ion-ion attraction force (principal intermolecular force).
[tex](CH_{3})_{3}N[/tex] is a polar covalent molecule. So dipole-dipole attraction force (principal intermolecular force) exists in this molecule.
We know, ion-ion attraction force is stronger than dipole-dipole attraction force. Therefore more energy is required to boil liquid [tex]K_{2}S[/tex] by disrupting stronger ion-ion attraction force as compared to [tex](CH_{3})_{3}N[/tex].
So, [tex]K_{2}S[/tex] has higher boiling point.
(b) Both [tex]Br_{2}[/tex] and [tex]CH_{3}CH_{2}CH_{2}CH_{3}[/tex] are nonpolar covalent compounds. Hence only london dispersion force(principal intermolecular force) exists in both molecules.
London dispersion force is proportional to molas mass of a molecule.
[tex]Br_{2}[/tex] has higher molar mass as compared to [tex]CH_{3}CH_{2}CH_{2}CH_{3}[/tex] . Therefore [tex]Br_{2}[/tex] has higher boiling point.
