Question map
Which of the following is/are state function / functions? 1. q + w 2. q 3. w 4. H - TS Select the correct answer using the code given below.
Explanation
In thermodynamics, a state function is a property whose value depends only on the current state of the system, not the path taken to reach it. Heat (q) and work (w) are path functions because their values vary depending on the specific process or sequence of changes. However, according to the First Law of Thermodynamics, the sum (q + w) equals the change in internal energy (ΔU), which is a state function. Similarly, enthalpy (H), temperature (T), and entropy (S) are all state functions. The expression H - TS represents the Gibbs free energy (G), which is a fundamental thermodynamic potential and a state function. Therefore, while q and w individually are path-dependent, the combinations (q + w) and (H - TS) are independent of the path and qualify as state functions.
Sources
- [1] https://en.wikipedia.org/wiki/Table_of_thermodynamic_equations