Question

A thermodynamic state function is a quality:
A. used to determine heat changes
B. whose value is independent of path
C. used to determine pressure volume work
D. whose value depends on temperature only

Answer 1

Hint: Functions like pressure, volume, temperature etc. depend only on the state of a system and not on the path. Its value depends on initial and final states, hence independent of the path followed from one state to another.

Complete answer:
Thermodynamics is a branch of physics which deals with the relation between heat or other forms of energy. It transfers energy from one place to another and from one form to another.In thermodynamics the function of state , state quantity, or state variable is a property of a system that depends only on the current system but not on the way in which the system acquired that state.

A state function describes the equilibrium state of a system. A thermodynamic state function is a quantity whose value is independent of a path. Hence functions like pressure, volume, temperature etc. depend only on the state of a system and not on the path.

Therefore the correct option is B.

Additional Information:
List of state functions: Mass, energy, entropy, pressure, temperature, volume,chemical composition, specific volume, density and particle number.

Note: Remember the change in internal energy of the system is independent of the path. Internal energy, enthalpy and entropy are the examples of different state qualities as these qualities describe the equilibrium state of a thermodynamic system.