第2章物理化学(双语)

The zeroth law of thermadynamics
Two systems that are each found to be in thermal equilibrium with a third system will be found to be in thermal equilibrium with each other.
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Physical Chemistry
Chapter 2
Internal Energy内能
Internal energy内能: Total amount of energy in a
system. The sum total of all kinetic and potential energy within the system.
Physical Chemistry
Chapte 2
Chapter 2 THERMODYNAMICS热力学
extensive intensive Thermodynamic Properties composition volume pressure
Pressure（压力）: mechanical equilibrium Temperature（温度）: thermal equilibrium
Bilingual Course of Yunnan Open University
Physical chemistry
Chemical Engineering faculty of Yunnan Open University
Li Qin (associate professor)
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Chapter 2
chemical change, not the rate of chemical change.
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Physical Chemistry
Thermodynamic Systems 热力学系统
Considers the relationship between the system and the surroundings.系统和环境之间关系 System: The reaction, process or organism under study Surroundings环境: The
Energy transfer Closed system
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Physical Chemistry
System and Surroundings
1. Open system
2. Closed system
3. Isolated system
No matter transfer
No matter transfer
dw Fx dx
Reversible P-V Work dwrev = -PdV
1
closed system, reversible process
wrev 2 PdV
closed system, reversible process
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Physical Chemistry
Chapter 2
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Physical Chemistry
Chapter 2
Thermodynamic Properties热力学性质
Extensive property（广度性质）： The value of the property changes according to the amount of material which is present Intensive property（强度性质）：independent of the amount of material which is present State functions（状态函数）: the value of a particular property for a system depends solely on the state of the system at time Path functions（过程函数）: A property depends upon the path by which a system in one state is changed into another state.
Heat（热）: the transfer of energy as disorderly motion as the result of a temperature difference between the system and its surroundings.
exothermic（吸热）: a process that releases energy as heat (all combustion reactions)
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Physical Chemistry
Chapter 2
2.2 The First Law of Thermodynamics 热力学第一定律
Isothermal: 等温
Basic Concepts 基本概念
A system which is held at constant temperature Adiabatic绝热: A system in which energy may be transferred as work, but not as heat.
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Physical Chemistry
Chapter 2
Work功
Work: the transfer of energy as orderly motion
due to energy being expanded against an opposing force (in mechanical terms)
Internal energy changes内能变化: The sign of U
Negative values（负值）: a system loses energy to the surroundings Positive values（正值）: a system gains energy from the surroundings
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Physical Chemistry
THERMODYNAMICS 热力学
Walls: rigid or nonrigid (movable)边界 Walls: permeable or impermeable A
W
B
Walls: adiabatic or nonadiabatic (thermally conducting)
(b)
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Physical Chemistry
Chapter 2
Heat: the transfer of energy as disorderly motion as the result of a temperature difference between the system and its surroundings. endothermic吸热: energy enters as heat from the surroundings, the system remains at the same T (c) exothermic放热: energy leaves as heat from the system, the system remains at the same T (d) a diathermic container绝热 An isothermal process
endothermic（放热）: processes that adsorb energy as heat(the vaporization of water) an adiabatic system绝热系统
(a) an endothermic process
(a)
(b) an exotsible P-V Work可逆体积功
dx V Piston moving (a) Expansion (dV > 0) V Piston moving (b) Compression (dV < 0)
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Fx=F=PA
dx
Fx=F=PA
Physical Chemistry
Chapter 2
mechanical equilibrium Equilibrium material equilibrium thermal equilibrium phase equilibrium
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Physical Chemistry
Thermodynamic Properties
Equilibrium 平衡 Mechanical Equilibrium 力平衡 No unbalanced forces act on or within the system No acceleration, no turbulence within the system Material Equilibrium 物质平衡 No net chemical reactions are occurring in the system No net transfer of matter, the concentrations of the chemical species are constant in time Thermal Equilibrium 热平衡 No change in the properties of the system or surroundings when they are separated by a thermally 10 conducting wall.
No energy transfer
No energy 7 transfer
Physical Chemistry