Chem Unit 7

Intermolecular Forces (IMF)

Intramolecular

a chemical bond within a single molecule

Intermolecular

an attractive force between neighboring molecules

What creates a dipole?

one atom attracting electrons stronger, causing shared electrons to be pulled towards it

Polar

a molecule lacks symmetry around the central atom

Dipole-Dipole Attraction

Molecules that have permanent dipoles are attracted to each other (positive → negative)

Hydrogen Bond

Dipole-dipole interaction bonding H and N. O, or F

London Dispersion Forces

Temporary attractions between an instantaneous dipole and an induced dipole

Momentary Dipole

a momentary imbalance of electrons (clumps)

Dispersion Forces

Dipole-dipole interactions among momentary dipoles

Van Der Waal Forces

dispersion forces

What IMF do nonpolar molecules usually use?

London Dispersion Forces

What IMF do polar molecules usually use?

Dipole-dipole attraction