intermolecular forces

London dispersion forces

-attraction between 2 instantaneous dipoles -asymmetrical electron distribution -all atoms & molecules relative strength : weak -increases in strength as molar mass increases

dipole-dipole forces

-attraction between 2 permanent dipoles -polar molecules relative strength : medium -stronger when molecules are closer together

hydrogen bonding

-attraction between molecules with N-H, O-H, & F-H bonds -extremely polar bonds --> very strong dipole-dipole force relative strength : strong -NOT CHEMICAL BONDING

intermolecular forces

forces of attraction between molecules

bonds

no ______________ are broken when a molecular substance changes state

ions, ionic, forces

the forces holding _____ together in _________ solids are ionic electrostatic forces. opposite charges attract each other. these are the strongest intraparticle __________

higher

the more polar the molecule, the _______________ its boiling point

stronger

the more polar the molecule, the __________________ its intermolecular forces

London Dispersion Forces

the strongest intermolecular forces in a sample of oxygen gas are the __________________

intermolecular forces are forces that exist between molecules. intramolecular forces are forces that hold atoms together within a molecule.

what is the difference between intermolecular forces and intramolecular forces?

the greater the element weighs, the higher the boiling point is. the intermolecular forces are stronger in these compounds

what is the relationship between molecular weight and boiling point?

unchanged

when a molecular substance changes state, the atoms within the molecules are ________________

nonpolar

C2H6

nonpolar

CH4

polar

H2O

polar

HCl

polar

HF

unequal, charges

__________ sharing of electrons in a molecule results in the formation of partial _______________ on the molecule

dipole

a ___________ occurs because one part of a molecule has a partial positive charge while another part of a molecule has a partial negative charge

increases

as the molar mass of a compound increases, the strength of its intermolecular forces ________________

F, O, N

compounds containing a hydrogen atom bonded to the elements __, ___, ___, form very strong intermolecular forces. These forces are called hydrogen bonds.

hydrogen bonding in H2O occurs between a hydrogen atom of one water molecule and the unshared pair of electrons an oxygen atom of the other water molecule. it is a particularly strong type of intermolecular force. hydrogen bonding causes the boiling point of the water to increase and so is the molar mass

describe hydrogen bonding as it occurs in water in terms of the location of the bond, the particles involved, the strength of the bond, and the effects this type of bonding has on physical and chemical properties.