State Functions / State Variables

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State functions are properties of a system that depend solely on its current state, not on how it arrived there. They are path independent, meaning the values can be determined without knowledge of the system's history. An example of a state function is enthalpy, which can be calculated from temperature and pressure without regard to the process taken to reach those conditions. In contrast, work is not a state function, as it is dependent on the specific path taken between two states. Understanding these distinctions is crucial for analyzing thermodynamic systems effectively.
luckymango
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State function - Properties of the system that are independent of the history of the system. The values of these variables can be calculated from knowledge of the present state of the system, without knowing its history.

Can someone clarify that?? I'm not getting what a state function is...
 
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A state function means it is path independent. It does not matter how you get there.
 
Can you explain using an example?? Sorry for the hassle...
 
enthalpy is a state function: if you know the temperature and pressure you know the enthalpy. It does not matter how you get to that temperature and pressure.

Work, on the other hand is not a state function. The intergral of the work does not depend on the end conditions, but on the path between those end conditions.

http://en.wikipedia.org/wiki/State_function
 
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