Intermolecular Forces v polar v This symbol means
Intermolecular Forces
v polar v Ø This symbol: means “partial. ” Ø This type of arrow: → | is a “dipole. ” + H Cl
v dipole negative DI – POLE = two - poles + Positive Pole H Cl Negative Pole
v Ø B AB 3 NO net dipole moment A B B
v Ø O H 2 O H H net dipole moment
v Ø Ø H CHCl 3 Cl Cl Cl net dipole moment
v Ø This ATTRACTIO N between the molecules is the IMF.
v v Ø attracts
v v Charge attraction between permanent dipoles All polar molecules Medium strength It is stronger when the molecules are closer.
v temporary Ø Ø unevenly
v dipole temporary Ø temporary dipole
v Ø temporary or instantaneous (only lasting for an instant) attractions.
v v Instantaneous attraction between temporary dipoles due to uneven e- dispersion All atoms & molecules v Weakest strength v Stronger for molecules with greater masses.
v Ø extremely polar bonds Ø force dipole-dipole
v Ø Ø Ø directly
v v v Extreme attraction between molecules with N-H, O-H, or F-H bonds. Molecules with H bound directly to N, O, F Greatest strength v Sometimes called a “pseudo bond”, but it is NOT chemical bonding.
LD DD HB LD DD -- LD -- -- LD DD --
LD DD HB LD -- -- LD -- HB LD DD HB
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