Definition of State Function?

Question

I'm having trouble understanding the concept of a state function, particularly relating to enthalpy, which is, and heat and work, which are not. I don't understand the why of this very well.

Answer 1

in simple terms; it does not matter how many steps it took to get to the end, what matters are the first and last points.

for example: when travelling in a circle, your distance is the circumfrence of the circle and the DISPLACEMENT is ZERO because you started and ended in the same place.
Displacement is a state function.

second example: Hess's Law, a set of chemical reactions are added together to make one overall equation. A set of reactants forms products, and those products are reactants for another reaction that also occurs, these are elementary steps, or intermediates. The end product, where the products are not reacting further in another reaction. The OVERALL chemical equation does not take into account the elementary steps, it only shows the initial reactants and the final products. Thus, it is a state fuction.

Answer 2

In thermodynamics, a state function, or state quantity, is a property of a system that depends only on the current state of the system, not on the way in which the system got to that state. A state function describes the equilibrium state of a system. For example, internal energy, enthalpy and entropy are state quantities because they describe quantitatively an equilibrium state of thermodynamic systems. At the same time, mechanical work and heat are process quantities because they describe quantitatively the transition between equilibrium states of thermodynamic systems.

Answer 3

I haven't the foggiest. To me a state function is party put on by the Governor or President.