1. Kintetic Molecular Theory
Phases of Matter
Kintetic Molecular Theory

2. Phases of Matter
Mr Kent’s Chemistry Page
Phases of Matter Animation

3. Phases of Matter
WebVision Animation Particle Motion in Phases of Matter

4. Phases of Matter
WebVision Animation Particle Motion in Phases of Matter

5. Phases of Matter
Sodium Acetate Crystals

6. Types of Intermolecular Forces
The boiling point and the melting point of a substance depend on the strength of the intermolecular forces.
The stronger the attractive force the higher the boiling point and the melting point temperature.

7. Dispersion Forces (Van der Waals Forces)
- the attraction between molecules caused by
oppositely charged ends of the compound
(a temporary condition – temporary dipole).
Draw example diagram
an attractive force that exists between all molecules.
the strength of the dispersion force increases with
increasing atomic size,
increasing mass
and decreasing distance between molecules.
The melting and boiling points increase with increasing atomic size & mass.

8. Dipole-Dipole Forces
attractions between opposite charges of neighboring permanent dipoles (polar molecules)
Draw example diagram

9. Hydrogen Bonding
occurs between molecules of any compound in which hydrogen is bonded to fluorine, oxygen, or nitrogen.
These are the three most electronegative nonmetals,
(F – 4.0, O – 3.4, N – 3.0)
and have the strongest attraction for electrons and hydrogen has a much lower electronegativity (H- 2.2) creating a large difference in pull for the electrons and large partial charges on the atoms of these molecules.

10. The large partial charges result in extremely strong
dipole-dipole force.
Hydrogen bonds are stronger than
dispersion or dipole-dipole forces.
Molecules with hydrogen bonds have
higher boiling and melting points.

11. Water Dihydrogen sulfide
H2O has a higher boiling point than H2S because of hydrogen bonding.
BPH2O = 100 ºC

12. Surface Tension - the imbalance of forces at the surface of a liquid.
The stronger the intermolecular forces of attraction,
the greater the surface tension.

13. Some Unique Properties of Water:
high boiling point _____________
high specific heat _____________
density of solid state of water (ice) is less than density of liquid state
( g/ml) ( g/ml)
high surface tension
high heat of vaporization
excellent solvent because of polar nature of molecule
Use your notes and Read p in textbook to complete worksheets: 13-1 and 13-2 Review & Reinforcement

14. Some Unique Properties of Water:
high boiling point °C
high specific heat
density of solid state of water (ice) is less than density of liquid state
( g/ml) ( g/ml)
high surface tension
high heat of vaporization
excellent solvent because of polar nature of molecule
Use your notes and Read p in textbook to complete worksheets: 13-1 and 13-2 Review & Reinforcement

15. Some Unique Properties of Water:
high boiling point °C
high specific heat J/g °C
density of solid state of water (ice) is less than density of liquid state
( g/ml) ( g/ml)
high surface tension
high heat of vaporization
excellent solvent because of polar nature of molecule

16. Some Unique Properties of Water:
high boiling point °C
high specific heat J/g °C
density of solid state of water (ice) is less than density of liquid state
( g/ml) ( g/ml)
high surface tension
high heat of vaporization
excellent solvent because of polar nature of molecule
Use your notes and Read p in textbook to complete worksheets: 13-1 and 13-2 Review & Reinforcement