Question

SOIL II2Lfs Highest D.P. o. Predict which substance in each of the following pairs would have the greater intermolecular forces. a.CO2 or OCS b.SeO2 or SO2 c. CH3CH3 or H,CO d. CH3OH or HCO

Answer 1

(a)

CO2 (O=C=O) is Nonpolar so it have only London disperson forces between molecules.

Where as OCS ( O=C=S) is Polar molecule so it will have dipole dipole forces between molecules.

Dipole dipole interactions are strong interactions than disperson forces.

Hence, OCS has greater intermolecular forces.

(b)

SeO2 and SO2 both are polar and having same geometry. But SeO2 is larger molecule than SO2.

Hence SeO2 has greater intermolecular forces.

(C)

CH3CH3 and H2CO

CH3-CH3 is non polar molecule so it has only London disperson forces.

H2CO is Polar molecule so it has dipole dipole interactions.

Hence, H2CO has greater intermolecular forces.

(d)

CH3OH is Polar and it form hydrogen bonds between molecules.

H2CO is Polar and it has dipole dipole interactions between the molecules.

Hydrogen bond is strong force than dipole dipole interactions.

Hence CH3OH has greater intermolecular forces.