Question

Among the state function (s) is (are):
A.Internal Energy
B.Irreversible expansion work
C.Reversible expansion work
D.Molar enthalpy

Answer 1

Hint: State function is the property of a system which does not depend on the path followed by the system and depends only on the initial and final state of the system.

Complete step by step answer:
A thermodynamic system can be described by a number of thermodynamic parameters such as pressure, volume, temperature, internal energy, enthalpy etc. These can be divided in to state functions and path functions.
A state function is a property of a system whose value depends upon the initial and final states of the system. It is also known as point function. These types of functions describe an equilibrium state of a function and does not depend on how the system arrived in that state.
For example, Internal energy is considered as a state function and is independent on the path followed to change the state of the system. It is the total energy of a system. This is made up of a number of components such as translational kinetic energy of molecules, bond energy, electronic energy, intermolecular interaction energy of the constituents particles of the system etc. Internal energy is a function of pressure, volume, temperature etc. These all variables are state functions.
Similarly, molar enthalpy is also a state function. Enthalpy is the sum of internal energy and pressure volume or work. It is defined in terms of state functions.
Path function is a property of a system whose value depends upon the path followed.
Heat and Work are path functions. Exchange of energy between system and surrounding can occur in the form of work. This may be mechanical or electrical.

Hence the correct answer is A and D.

Note:
Other examples of state function include mass, volume, pressure, temperature, density, entropy etc. There are some variables that depend upon the amount of matter present. These are known as Extensive properties. Examples include mass, volume etc. Some other variables are independent of the amount of matter known as intensive properties. Examples, density.