IMFA

• A polar molecule is molecule in which one end of the molecule is slightly positive, while the other end is slightly negative
• A polar molecule contains dipole-dipole and LDF forces
• Stronger intermolecular forces lead to:

  • higher melting point
  • higher boiling point
  • greater surface tension
  • greater viscosity
  • lower vapor pressure
• Hydrogen bonding occurs when hydrogen is attached to an atom with high electronegativity such as fluorine, oxygen, or nitrogen
• Na+, Cl-, and OH- are examples of Ion-Ion force.
• Ion-Ion force is present between ions and is the strongest intermolecular force. They are easily recognized because they have a charge.
• The stronger the intermolecular forces, the higher the boiling point will be.
• Ion-Dipole forces have both ion and polar molecules.
• Ion-Dipole forces are weaker than Ion-Ion forces but stronger than Dipole-Dipole forces.
• Dipole-Dipole forces occur when two polar molecules attract one another due to their opposite charges.
• Ion-Dipole forces occur when there is an attraction between oppositely charged particles (ion) and dipoles (polar).
• London dispersion forces are also known as Van Der Waal's forces
• Dipole-Dipole forces occur when two polar molecules interact with one another.
• $H_2O$ and $H_2O$ have the following IMFA's: LDF, Hydrogen bond, and Dipole-dipole
• Water is an excellent solvent for ionic compounds because its polar nature allows it to surround and separate charged particles.
• Ionic bonds and covalent bonds are atomic bonds, meaning they are intramolecular
• $NaCl$ and $H_2O$ have the following IMFA's: LDF, Ion-Dipole
• If a structure is nonpolar, it will have LDF only
• If a structure is polar, it can be hydrogen bond and dipole-dipole
• Hydrogen bond is just a stronger type of dipole-dipole force
• If particles have the same IMFA's, the larger number of electrons and molar mass, the stronger the IMFA
• If a structure is symmetrical, it is nonpolar
• If a structure is asymmetrical, it will be polar
• If you have a structure with only C and H, the structure will always be nonpolar
• Intermolecular forces are the force of attraction present between molecules
• Intermolecular forces are present in covalent bonds
• An ionic compound consists of a positive ion and a negative ion
• An Ion-Dipole happens when an Ion and a nearby polar molecule (a dipole) attract each other
• Water is a polar molecule
• Ionic compounds are soluble in water because of ion-dipole forces
• When sodium chloride ($NaCl$) dissociates in water ($H_2O$), the sodium ion ($Na^+$) attracts the partially negative oxygen of the water molecules. The chlorine ion ($Cl^-$) attracts the partially positive hydrogen of water
• HCL and HCL have a dipole-dipole force
• $NaCl$ and water is an example of Ion-Dipole forces at work
• Hydrogen bonding is a special type of dipole-dipole force that exists between a hydrogen atom bound to a highly electronegative nonmetal atom
• Hydrogen bonding is weaker than a covalent bond and ionic bond
• Octane, nitrogen, carbon dioxide, chlorine, and the noble gases are example of nonpolar molecules
• London Dispersion Force is the attraction between the instantaneous dipole and the induced dipole in nonpolar molecules
• Dispersion forces are weak and are the dominant type of intermolecular forces between identical diatomic molecules like $O_2$, $N_2$, and $Cl_2$
• The intermolecular forces influence the physical properties of the three basic phases of matter: gas, liquid, and solid
• Gases have negligible intermolecular force existing between their molecules