Why does propanol have a higher boiling point than propanone, propanal or methyl ethanoate?

Molecules of propanol have a hydrogen directly bonded to a NOF atom (oxygen in this case), which means that they can hydrogen bond with eachother. The oxygen in the other three molecules is only bonded to a carbon atom so hydrogen bonding is not possible. All the molecules have Van der Waals forces between them but propanol has the addition of having hydrogen bonding, which is slightly stronger. The stronger forces between molecules means that more energy is required to break apart the molecules and therefore the substance has a higher boiling point. Remember boiling point is the temperature that corresponds to the energy required to break the intermolecular forces of attraction.