a) H2 H2 is nonpolar and thus only involves intermolecular London dispersion force; while CO is a polar molecule that involves both London dispersion force and dipole-dipole force. Thus, intermolecular forces between H2 is weaker than those between CO. Thus, H2 has a lower b.p. b) CO2 SiO2 is covalent compound that has very high b.p. NH3, PH3, CO2 are molecular compounds. NH3 and PH3 involves Hydrogen bonds. Thus, their b.p. are higher than that of CO2 Solution a) H2 H2 is nonpolar and thus only involves intermolecular London dispersion force; while CO is a polar molecule that involves both London dispersion force and dipole-dipole force. Thus, intermolecular forces between H2 is weaker than those between CO. Thus, H2 has a lower b.p. b) CO2 SiO2 is covalent compound that has very high b.p. NH3, PH3, CO2 are molecular compounds. NH3 and PH3 involves Hydrogen bonds. Thus, their b.p. are higher than that of CO2.

1. a) H2 H2 is nonpolar and thus only involves intermolecular London dispersion
force; while CO is a polar molecule that involves both London dispersion force and dipole-dipole
force. Thus, intermolecular forces between H2 is weaker than those between CO. Thus, H2 has a
lower b.p. b) CO2 SiO2 is covalent compound that has very high b.p. NH3, PH3, CO2 are
molecular compounds. NH3 and PH3 involves Hydrogen bonds. Thus, their b.p. are higher than
that of CO2
Solution
a) H2 H2 is nonpolar and thus only involves intermolecular London dispersion
force; while CO is a polar molecule that involves both London dispersion force and dipole-dipole
force. Thus, intermolecular forces between H2 is weaker than those between CO. Thus, H2 has a
lower b.p. b) CO2 SiO2 is covalent compound that has very high b.p. NH3, PH3, CO2 are
molecular compounds. NH3 and PH3 involves Hydrogen bonds. Thus, their b.p. are higher than
that of CO2