แรงกระทำระหว่างโมเลกุล (Intermolecular Forces)
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Transcript of แรงกระทำระหว่างโมเลกุล (Intermolecular Forces)
แรงกระทำ��ระหว่��งโมเลก�ล (Intermolecular Forces)
เนื้��อห�ทำ��จะเร�ยนื้1 Intermolecular Forces and some Properties of Liquids
2 Vaporization of Liquids: Vapor Pressure
3 Some Properties of Solids
4 Phase Diagrams
5 Van der Waals Forces
6 Hydrogen Bonding
7 Network Covalent Solids and Ionic Solids
Cohesive Forces Intermolecular forces between like molecules.
Adhesive Forces Intermolecular forces between unlike molecules.
Surface Tension Energy or work required to increase the surface area
of a liquid. Viscosity
A liquids resistance to flow
Intermolecular Forces and Some Properties of Liquids
Intermolecular Forces
Intermolecular Forces
Vaporization of Liquids:Vapor Pressure
ΔHvap = Hvapor – Hliquid = - ΔHcondensation
Boiling Point
Mercury manometer
Vapor pressure of liquid
Pvap independent
of Vliq
Pvap independent
of Vgas
Pvap dependent on
T
Vapor Pressure and Boiling Point
Vapor Boils at Low Pressure
The Critical Point
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(a) liquid only(b) vapor only(c) liquid-vapor equilibrium
Clausius-Clapeyron Equation
ln = - ( - ) P2
P1
1T2
1T1
ΔHvap
R
ln P = -A ( ) + B1T
A = ΔHvap
R
Some Properties of Solids
Freezing Point
ΔHfus(H2O) = +6.01 kJ/mol
Melting Point
Sublimation
ΔHsub = ΔHfus + ΔHvap
= -ΔHdeposition
Phase Diagrams
Iodine
Phase Diagrams
Carbon dioxide
Supercritical Fluids
Decaffeination with Supercritical CO2
Water
Prentice-Hall © 2007General Chemistry: Chapter 12Slide 24 of 54
Interpreting a Phase Diagram
Van der Waals Forces
Instantaneous dipoles. Electrons move in an orbital to cause a polarization.
Induced dipoles. Electrons move in response to an outside force.
Dispersion or London forces. Instantaneous dipole – induced dipole attraction. Related to polarizability.
Phenomenon of Induction
Instantaneous and Induced Dipoles
< 10 kJ/mol
Dipole Dipole Interactions
5 to 20 kJ/mol
Prentice-Hall © 2007General Chemistry: Chapter 12Slide 29 of 54
Electrostatic Potential Maps
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เร�ย์งล-าด�บจ.ดเด3อดของสารต่�อไป็น��: CCl4, Cl2, ClNO, N2. จ.ดเด3อดท่��พิ่บ
จร�ง
CCl4 =
349.9 K
ClNO = 266.7 K
Cl2 = 239.1
K
N2 = 77.3 K
Hydrogen Bonding
15 to 40 kJ/mol
Hydrogen Bonding
Hydrogen Bonding in HF(g)
Hydrogen Bonding in Water
around a molecule in the solid in the liquid
Other examples of H-Bonds
DNA Double Helix
The Polymerase Chain Reaction (PCR)
Network Covalent Solids and Ionic Solids
Other Carbon Allotropes
Interionic Forces
Energy Changes in the Formation of Ionic Crystals
Ion-dipole Interactions
cation- Interactions
anion- Interactions
- Interactions
Hydrophobic Effects
Focus On Liquid Crystals
Liquid Crystal Thermometers
End of Chapter Questions
If I had the answer, what would I have used to get it.
You can think about problems in reverse to help sort out a strategy.
a
b
c