London dispersion forces Dipole-dipole
- weakest imf -dipole: when 1 end negative,
-what affects strength? other positive
- size of molecule and shape - dipole moment: when 1 cmpd
- larger molecules = has diff electronegs.
stronger lf - d moments created within
-affected most by weight cmpd may cancel if
-elongated vs compact symmetric
more likely to have lf b/c -ionic charges have strong
more space for lf to occur dipole moments b/c opp.
- molecules with only this tend Charges
to have higher vp, lower - ie: hcl, hf
Hvap, low meltint point and -stronger electronegativity
bp = stronger dipole attraction
- only important when no other -stronger dipole moments =
imf is present higher bp
-non polar covalent molecules - d moments large to small:
(br2) or single atoms (na2+) ionic > asymmetric >
are examples of molecules symmetric
that lack other imf but ldf - polar covalent bond- when
2 bonded atoms unequally
Hydrogen bonding share electrons (ie: pi)
- when h bonded to n, o, f -nonpolar covalent- when
- +h attracts lone pair of they attract electrons w/
electroneg atoms Equal strength (ie: cl-cl)
- # of h bonds per molecule -in general: metal-nonmetal
affects strength combination is ionic.
L
In general Nonmetal-nonmetal is
- strong imf = covalent.
- lower vp -if no electroneg value
-higher Hvap given, assume covalent
-higher melting point bond is polar unless b/w 2
-higher boiling point atoms of same element
, _
- higher viscosity
Molecular compounds
- higher surface- made up of nonmetals
tension - atoms held together by
covalent bonds
Transformation between 3 -share electrons
physical states - intramolecular forces =
- solid —> liquid = melting/fusion covalent bond. Happens
- liquid —> gas = vaporization between atoms
- gas —> liquid = condensation -intermolecular force = h-
- liquid —> solid = freezing bond, ldf, dipole dipole.
- solid —> gas = sublimation Happens between
-gas —> solid = deposition molecule
- dynamic equilibrium: when - intermolecular forces only
rates of 2 states (ie: liquid&gas) happens here
are equal & p of vapor is
constant Ion- dipole force
- both states much exist (IE: - Origen: when ionic cmpd
condensation & vaporization) mixes w/ polar solvent,
Ionic compounds ions are attracted to opp.
- made up of cations and anions Charged end of solvent
(metals and nonmetals) molecules
-no distinction b/w intra and - why some ionic cmpd
inter molec. Forces form solution w/ water
- atoms held together by (like nacl)
electrostatic attraction - charge of ion and polarity
- attractive forces b/w cations of solvent molecule
and anions is ionic bond affects strength
Metals
- atoms donate their valence
electrons to make pool of e-
-attractive force called
metallic bond
- no distinction b/w intra and
inter forces
- weakest imf -dipole: when 1 end negative,
-what affects strength? other positive
- size of molecule and shape - dipole moment: when 1 cmpd
- larger molecules = has diff electronegs.
stronger lf - d moments created within
-affected most by weight cmpd may cancel if
-elongated vs compact symmetric
more likely to have lf b/c -ionic charges have strong
more space for lf to occur dipole moments b/c opp.
- molecules with only this tend Charges
to have higher vp, lower - ie: hcl, hf
Hvap, low meltint point and -stronger electronegativity
bp = stronger dipole attraction
- only important when no other -stronger dipole moments =
imf is present higher bp
-non polar covalent molecules - d moments large to small:
(br2) or single atoms (na2+) ionic > asymmetric >
are examples of molecules symmetric
that lack other imf but ldf - polar covalent bond- when
2 bonded atoms unequally
Hydrogen bonding share electrons (ie: pi)
- when h bonded to n, o, f -nonpolar covalent- when
- +h attracts lone pair of they attract electrons w/
electroneg atoms Equal strength (ie: cl-cl)
- # of h bonds per molecule -in general: metal-nonmetal
affects strength combination is ionic.
L
In general Nonmetal-nonmetal is
- strong imf = covalent.
- lower vp -if no electroneg value
-higher Hvap given, assume covalent
-higher melting point bond is polar unless b/w 2
-higher boiling point atoms of same element
, _
- higher viscosity
Molecular compounds
- higher surface- made up of nonmetals
tension - atoms held together by
covalent bonds
Transformation between 3 -share electrons
physical states - intramolecular forces =
- solid —> liquid = melting/fusion covalent bond. Happens
- liquid —> gas = vaporization between atoms
- gas —> liquid = condensation -intermolecular force = h-
- liquid —> solid = freezing bond, ldf, dipole dipole.
- solid —> gas = sublimation Happens between
-gas —> solid = deposition molecule
- dynamic equilibrium: when - intermolecular forces only
rates of 2 states (ie: liquid&gas) happens here
are equal & p of vapor is
constant Ion- dipole force
- both states much exist (IE: - Origen: when ionic cmpd
condensation & vaporization) mixes w/ polar solvent,
Ionic compounds ions are attracted to opp.
- made up of cations and anions Charged end of solvent
(metals and nonmetals) molecules
-no distinction b/w intra and - why some ionic cmpd
inter molec. Forces form solution w/ water
- atoms held together by (like nacl)
electrostatic attraction - charge of ion and polarity
- attractive forces b/w cations of solvent molecule
and anions is ionic bond affects strength
Metals
- atoms donate their valence
electrons to make pool of e-
-attractive force called
metallic bond
- no distinction b/w intra and
inter forces
