Path/process (I) Final state Initial state Path/process (II) The characteristics of a state function: (1)the value of a state function is unique when the state of a system is specified. (2)the change in the value of a state function depends only on an initial state and a final state of a system and is independent of the path(途径) /process(过程)between the two states.(2) the change in the value of a state function depends only on an initial state and a final state of a system and is independent of the path (途径) /process(过程) between the two states. Initial state Final state Path/process (II) Path/process (I) The characteristics of a state function: (1) the value of a state function is unique when the state of a system is specified