Question

a state function is best described as
answer:
a a function that depends on what is taken between start and finish.
b a function that is independent of the amount of substance.
c a function that depends only on the starting point and ending point of a process.
d a function that only depends on the end point of a process.

Explanation:

A state function is a property whose value does not depend on the path taken to reach that specific value. It only depends on the initial and final states of the system. For example, internal energy (\(U\)), enthalpy (\(H\)), and entropy (\(S\)) are state functions. If a system changes from state \(A\) to state \(B\), the change in a state function (e.g., \(\Delta U=U_B - U_A\)) is determined solely by the values of the function at \(A\) and \(B\), not on how the system got from \(A\) to \(B\).

• Option A: A state function is not path - dependent. So, this option is incorrect.
• Option B: The property described in option B is an intensive property (e.g., temperature, pressure). A state function can be either intensive or extensive. For example, internal energy (\(U\)) is extensive (depends on the amount of substance) and is a state function. So, this option is incorrect.
• Option C: This is the correct definition of a state function as it depends only on the starting and ending points of a process.
• Option D: A state function depends on both the starting and ending points. So, this option is incorrect.

Answer:

C. a function that depends only on the starting point and ending point of a process.