Terms for Unit 3 - Chemistry

intramolecular force

a force that exists within a molecule

bond

name of intramolecular force

intermolecular force

forces of attraction BETWEEN molecules

London dispersion forces

attractions of protons in one molecule or atom temporarily attracting electrons in another molecule or atom

size (larger = more ldfs)

shape (long/skinny = more ldfs because of surface area)

what are LDFs determined by?

all of them

which substances have LDFs?

temporary dipole

an intermolecular force between nonpolar molecules caused by the presence of temporary dipoles within the molecules

(the gif is a good representation of this…)

permanent dipole

permanent separation of electrical charge in a molecule due to unequal distributions of bonding and/or lone pairs of electrons

dipole-dipole forces

attraction between positive part of one polar molecule to the negative part of another molecule

strong type of intermolecular dipole-dipole attraction. Occurs between hydrogen and F, O or N

Hydrogen bonding

dipole-induced dipole forces

a type of intermolecular interaction that occurs between a polar molecule (which has a permanent dipole) and a nonpolar molecule (which does not have a permanent dipole)

ion-dipole forces

(when something that makes ions dissolves in something polar) attractive forces between an ion and a polar molecule

gas

weak IMFs

solid

strong IMFs

boiling point

More polar the molecule, the higher the…

London, dipole

If molecular weight is about the same, they have about the same # of protons and electrons (___ forces are about the same) - but _ forces can be different