In: Chemistry
EXAMPLES OF THERMODYNAMIC STATE FUNCTION WITH DEFINITION
A thermodynamic state function is defined as a property whose value does not depend on the path taken to reach that specific function or value. The system is thus at equilibrium. The examples of thermodynamic state functions are internal energy, enthalpy, state of the system, etc. In general a "State" refers to temperature, pressure, and the amount and type of substance present. Once the state has been established, state functions can be defined. State functions are values that depend on the state of the substance, and not on how that state was reached.
For example, density is a state function, because a substance's density is not affected by how the substance is obtained. Consider a quantity of H2O: it does not matter whether that H2O is obtained from the tap, from a well, or from a bottle, because as long as all three are in the same state, they have the same density. When deciding whether a certain property is a state function or not, we consider the following rule, analyze If the property or value in consideration is affected by the path or way taken to establish it. If the answer is no, then it is a state function, but if the answer is yes, then it is not a state function.