版权所有：华东理工大学物理化学教研室 6 The First Law: dU =dq+dw H pV U pV A TS G TS For a reversible change in a closed system of constant composition, and in the absence o f a n y n o n - e x p a n s i o n work: d w = -pdV and dq =TdS dU=TdS-pdV dU is an exact differential, its value is independent of path. The fundamental equations版权所有：华东理工大学物理化学教研室 6 The First Law: dU =dq+dw H pV U pV A TS G TS For a reversible change in a closed system of constant composition, and in the absence o f a n y n o n - e x p a n s i o n work: d w = -pdV and dq =TdS dU=TdS-pdV dU is an exact differential, its value is independent of path. The fundamental equations