The direction of spontaneous change 4.1 The dispersal of energy In the term of entropy The entropy of an isolated system increases in the course of a spontaneous change >0 tot where stot is the total entropy of the system and its surroundings. Thermodynamically irreversible processes are spontaneous processes, and must be accompanied by an increase in entropy. 版权所有:华东理工大学物理化学教研
版权所有：华东理工大学物理化学教研室 11 The entropy of an isolated system increases in the course of a spontaneous change: In the term of entropy Stot 0 where Stot is the total entropy of the system and its surroundings. Thermodynamically irreversible processes are spontaneous processes, and must be accompanied by an increase in entropy. 4.1 The dispersal of energy The direction of spontaneous change
The direction of spontaneous change The characteristic of these two process spontaneous and non-spontaneous Is summarized by the second law of Thermodynamics 版权所有:华东理工大学物理化学教研
版权所有：华东理工大学物理化学教研室 12 The characteristic of these two process, spontaneous and non-spontaneous is summarized by the Second Law of Thermodynamics. The direction of spontaneous change
Statements on the Second Law of Thermodynamic The Second Law may be The First Law led to the intro expressed in terms of the duction of the internal energy, entropy, a state function a state function that lets us that lets us assess whether assess whether a change is one state is accessible from permissible; only those change another by a spontaneous may occur for which the U of change. the Second Law an isolated system remains uses the entropy to identify constant. First Law uses the the spontaneous changes internal energy to identify among those permissible permissible changes changes 版权所有:华东理工大学物理化学教研
版权所有：华东理工大学物理化学教研室 13 The Second Law may be expressed in terms of the entropy, a state function that lets us assess whether one state is accessible from another by a spontaneous change. the Second Law uses the entropy to identify the spontaneous changes among those permissible changes. The First Law led to the introduction of the internal energy, a state function that lets us assess whether a change is permissible; only those change may occur for which the U of an isolated system remains constant. First Law uses the internal energy to identify permissible changes; Statements on the Second Law of Thermodynamic
Statements on the Second Law of Thermodynamic No process is possible in which the sole result is the absorption of heat from a reservoir and its complete conversion into work The spontaneous changes are al ways accompanied by a dispersal of energy into a more disordered form The entropy of an isolated system increases in the course of a spontaneous change △S.>0 tot 版权所有:华东理工大学物理化学教研
版权所有：华东理工大学物理化学教研室 14 No process is possible in which the sole result is the absorption of heat from a reservoir and its complete conversion into work. The entropy of an isolated system increases in the course of a spontaneous change: Stot 0 The spontaneous changes are always accompanied by a dispersal of energy into a more disordered form. Statements on the Second Law of Thermodynamic
4. The Second Law: the concepts The direction of spontaneous change 4.1 The dispersal of ener 4.2 Entropy 4. 3 Entropy changes accompanying specific processes 4. 4 The Third Law of thermodynamics 4.5 Reaching very low temperatures Concentrating on the system 4.6 The Helmholtz and Gibbs energies 4.7 Standard molar Gibbs energies 版权所有:华东理工大学物理化学教研
版权所有：华东理工大学物理化学教研室 15 The direction of spontaneous change 4.1 The dispersal of energy 4.2 Entropy 4.3 Entropy changes accompanying specific processes 4.4 The Third Law of thermodynamics 4.5 Reaching very low temperatures Concentrating on the system 4.6 The Helmholtz and Gibbs energies 4.7 Standard molar Gibbs energies 4. The Second Law: the concepts