Identify the predominant type of intermolecular force in eachof the following compounds

intermolecular-force

#1

Identify the predominant type of intermolecular force in eachof the following compounds.
CHF3, OF2, HF, CF4
Rank the following compounds in order of decreasing vaporpressure.
CH3CH2CH2OH, CH4, CH3OH, CH3CH2OH

Answer:

Predominant type of force;
CHF3: polar; Dipole dipole forces
OF2: Polar; dipole dipole forces
HF: hydrogen bonding (H-F)
CF4: nonpolar; london/dispersion forces.

Weak intermolecular forces -> higher Vapor pressure
Lower mass -> higher vapor pressure
CH3CH2CH2OH:polar, hydrogen bonding, 60g/mol
CH4: nonpolar, dispersion, 16 g/mol
CH3OH: hydrogen bonding, polar 32 g/mol
CH3CH2OH: hydrogen bonding, polar 46 g/mol

Overall: CH4 > CH3OH > CH3CH2OH > CH3CH2CH2OH