how vapor pressure and boiling point are related to intermolecular for forces (forces between molecules)?

Intermolecular forces are attractive forces between molecules. The stronger they are, the more the molecules will attract each other. Boiling the compound will break the intermolecular forces, since gas particles don't exert forces on one another according to the Kinetic Molecular Theory of Gases. So the stronger the intermolecular forces, the higher the boiling point. Vapor pressure is the pressure of the gas above its liquid. So the higher the vapor pressure, the more molecules in the gas phase, the lower the boiling point and the weaker the intermolecular forces.

Ethanol has dipole-dipole forces

Acetic acid has Hydrogen bonding, which is the strongest kind of intermolecular force (excluding ionic bonds)

Water has Hydrogen bonding

Acetone has dipole-dipole forces

Increasing rates of evaporation:

Acetic Acid < Water < Ethanol < Acetone

Boiling Point:

Acetic Acid < Water < Ethanol < Acetone

Ionic compounds are formed between a metal and non-metal elements on the periodic table. They make an ionic bonds. Molecular compounds are formed between two or more non-metal elements. They make covalent bonds. Ionic bonds deal with the transfer of electrons. One element (usually the metal) donates or gives a certain number of electrons to the the other element (the non-metal). Some examples: NaCl, Ca3P2, K3N Covalent bonds deals with the sharing of electrons. Instead of completely giving away electrons, two non-metals will share them. Some examples are: O2, C3P4, etc Another thing to note: Ionic bonds - subscripts can be predicted for each compound (using the periodic table). Covalent bonds - the subscripts cannot be predicted.