![Page 1: Intermolecular Forces H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H (given in increasing strength)](https://reader038.vdocuments.us/reader038/viewer/2022102818/56649cfe5503460f949cf20d/html5/thumbnails/1.jpg)
Intermolecular ForcesH
O
H
H
O
H
H
O
HH
O
H
H
O
HH
O
HH
O
HH
O
H
H
O
H
H
O
H
H
O
H
H
O
H
(given in increasing strength)
![Page 2: Intermolecular Forces H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H (given in increasing strength)](https://reader038.vdocuments.us/reader038/viewer/2022102818/56649cfe5503460f949cf20d/html5/thumbnails/2.jpg)
1. London dispersion force (Weakest)
Occurs between NON-POLAR molecules.
• Atoms of a NP molecule equally share bonding e-.• normally no overall charge.
(O2, Cl2, CH4, C2H8)
H
C HH
H
+ +
![Page 3: Intermolecular Forces H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H (given in increasing strength)](https://reader038.vdocuments.us/reader038/viewer/2022102818/56649cfe5503460f949cf20d/html5/thumbnails/3.jpg)
At any given time, e- in a molecule are unevenly distributed – e- move.
Causes temporary dipoles (charged regions) to form, which leads to attraction between molecules.
H
C HH
H
δ+
δ-
![Page 4: Intermolecular Forces H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H (given in increasing strength)](https://reader038.vdocuments.us/reader038/viewer/2022102818/56649cfe5503460f949cf20d/html5/thumbnails/4.jpg)
+ + + +
F F F FF2F2
δ+ δ-
non - polar molecules
![Page 5: Intermolecular Forces H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H (given in increasing strength)](https://reader038.vdocuments.us/reader038/viewer/2022102818/56649cfe5503460f949cf20d/html5/thumbnails/5.jpg)
H
C H
CH4CH4
δ+ δ-
non - polar molecules
H
H
C H
H
H
H
temporarydipole
![Page 6: Intermolecular Forces H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H (given in increasing strength)](https://reader038.vdocuments.us/reader038/viewer/2022102818/56649cfe5503460f949cf20d/html5/thumbnails/6.jpg)
2. Dipole-Dipole
One atom of a molecule pulls the shared electrons closer than the other (unequal sharing).
+ + HClδ+δ-
Causes permanent negative and positive dipoles.
The polar ends attract other polar molecules.
![Page 7: Intermolecular Forces H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H (given in increasing strength)](https://reader038.vdocuments.us/reader038/viewer/2022102818/56649cfe5503460f949cf20d/html5/thumbnails/7.jpg)
Cl
HCl
H
polar molecules
δ+
δ-
δ-
δ+
permanentdipole
+ +
δ+δ-
![Page 8: Intermolecular Forces H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H (given in increasing strength)](https://reader038.vdocuments.us/reader038/viewer/2022102818/56649cfe5503460f949cf20d/html5/thumbnails/8.jpg)
3. Hydrogen bond (special dipole-dipole force)
• Very strong force.
• Any substance containing hydrogen bonded directly to O, N, or F.
• O, N and F pull extremely hard on the bonding electrons (VERY unequal sharing) - large dipoles.
![Page 9: Intermolecular Forces H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H (given in increasing strength)](https://reader038.vdocuments.us/reader038/viewer/2022102818/56649cfe5503460f949cf20d/html5/thumbnails/9.jpg)
H
O
H
HOH
H
OH
N
H
H
H
H
N
H
H
H
H
N
H
H
H
H
polar molecules
δ+δ-
δ+
δ+
δ-
δ+
δ+
δ-
δ+
![Page 10: Intermolecular Forces H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H (given in increasing strength)](https://reader038.vdocuments.us/reader038/viewer/2022102818/56649cfe5503460f949cf20d/html5/thumbnails/10.jpg)
4. Strong ionic attraction
Positive and negatively charged IONS held together by electrostatic (attraction) forces.
These electrostatic forces are extremely strong, giving ionic compounds very large melting and boiling points.
![Page 11: Intermolecular Forces H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H (given in increasing strength)](https://reader038.vdocuments.us/reader038/viewer/2022102818/56649cfe5503460f949cf20d/html5/thumbnails/11.jpg)
Dispersion Forces - weakest, temporary positive and negative attraction caused by moving electrons.
Dipole / Dipole - weak, permanent dipole attraction caused by one atom pulling electrons more strongly.
Hydrogen Bonding - strong permanent dipole attraction caused by O, N or F bonded to hydrogen.
Electrostatic Attraction - strongest force of attraction between positive and negative ions in ionic compound.
![Page 12: Intermolecular Forces H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H (given in increasing strength)](https://reader038.vdocuments.us/reader038/viewer/2022102818/56649cfe5503460f949cf20d/html5/thumbnails/12.jpg)
Electrostatic Attraction
Dipole forces OR Hydrogen bonding
Dispersion Forces
![Page 13: Intermolecular Forces H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H (given in increasing strength)](https://reader038.vdocuments.us/reader038/viewer/2022102818/56649cfe5503460f949cf20d/html5/thumbnails/13.jpg)
The Special Case for Water
![Page 14: Intermolecular Forces H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H (given in increasing strength)](https://reader038.vdocuments.us/reader038/viewer/2022102818/56649cfe5503460f949cf20d/html5/thumbnails/14.jpg)
Hydrogen-bonding holds water molecules together strongly.
Responsible for the higher than expected melting pointand boiling point.
![Page 15: Intermolecular Forces H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H (given in increasing strength)](https://reader038.vdocuments.us/reader038/viewer/2022102818/56649cfe5503460f949cf20d/html5/thumbnails/15.jpg)
![Page 16: Intermolecular Forces H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H (given in increasing strength)](https://reader038.vdocuments.us/reader038/viewer/2022102818/56649cfe5503460f949cf20d/html5/thumbnails/16.jpg)
![Page 17: Intermolecular Forces H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H H O H (given in increasing strength)](https://reader038.vdocuments.us/reader038/viewer/2022102818/56649cfe5503460f949cf20d/html5/thumbnails/17.jpg)
Because of H - bonding, ice forms unique crystal shape (six-sided), having an area greater than that liquid water.
Ice is less dense than water...most solids are more dense than their respective liquids.