What are state functions in chemical thermodynamics?

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A state function is a property that depends only on the current state of a system, not on how it reached that state. Examples include gravitational potential energy, thermal energy, and enthalpy, which are determined by specific parameters like position, temperature, and pressure. In contrast, frictional energy is not a state function because it depends on the path taken between two points. Clarification and examples helped in understanding the concept of state functions. The discussion concluded with a clearer understanding of state functions.
Karan Punjabi
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Guys I am getting confused that what is state function? People say if state changes then state function also changes. But my view is if that variable changes then only state changes and its not necessary when a state change will always lead to change of every state function.
 
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Karan Punjabi said:
Guys I am getting confused that what is state function? People say if state changes then state function also changes. But my view is if that variable changes then only state changes and its not necessary when a state change will always lead to change of every state function.
It is very hard to understand what you are saying. Can you please reword this in an alternate way? Maybe examples would help too.
 
I think I can explain state functions.
Things that are only dependent on the current state of the system are state functions.
Gravitational potential energy is a state function.It is determined by the position of the masses in your system.(On Earth the height above the ground.)
Thermal energy is a state function . Just knowing the temperature and the specific heat capacity you can figure it out.
Enthalpy is also a state function.It is dependent on the same things thermal energy depends and additionally on the volume and pressure of the system.
You can go on like this.Entropy and stuff like the other thermodynamic potentials are also a state function
The amount of frictional energy an object "loses" to the environment between two points is not only dependant on the two points.
It is not a state function because it depends on the path.

I suspect that did not help you much, but feel free to ask it again in a more specific way.
 
Tazerfish said:
I think I can explain state functions.
Things that are only dependent on the current state of the system are state functions.
Gravitational potential energy is a state function.It is determined by the position of the masses in your system.(On Earth the height above the ground.)
Thermal energy is a state function . Just knowing the temperature and the specific heat capacity you can figure it out.
Enthalpy is also a state function.It is dependent on the same things thermal energy depends and additionally on the volume and pressure of the system.
You can go on like this.Entropy and stuff like the other thermodynamic potentials are also a state function
The amount of frictional energy an object "loses" to the environment between two points is not only dependant on the two points.
It is not a state function because it depends on the path.

I suspect that did not help you much, but feel free to ask it again in a more specific way.
Yeah I understood about the state functions...now having a clear view to it...thank you
 
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