Unit of entropy is
JK–1 mol–1
J mol–1
J–1K–1 mol–1 v
JK mol–1
The correct option is (A) : JK–1 mol–1
Entropy change ΔS= \(\frac{q_{rev}}{T}\) ∴The unit of entropy is JK−1mol−1
Consider the following statements:
(A) Availability is generally conserved.
(B) Availability can neither be negative nor positive.
(C) Availability is the maximum theoretical work obtainable.
(D) Availability can be destroyed in irreversibility's.
List-I (Details of the processes of the cycle) | List-II (Name of the cycle) |
---|---|
(A) Two adiabatic, one isobaric and two isochoric | (I) Diesel |
(B) Two adiabatic and two isochoric | (II) Carnot |
(C) Two adiabatic, one isobaric and one isochoric | (III) Dual |
(D) Two adiabatics and two isothermals | (IV) Otto |
Thermodynamics in physics is a branch that deals with heat, work and temperature, and their relation to energy, radiation and physical properties of matter.
The first law of thermodynamics, also known as the Law of Conservation of Energy, states that energy can neither be created nor destroyed; energy can only be transferred or changed from one form to another.
The second law of thermodynamics says that the entropy of any isolated system always increases. Isolated systems spontaneously evolve towards thermal equilibrium—the state of maximum entropy of the system. More simply put: the entropy of the universe (the ultimate isolated system) only increases and never decreases.
The third law of thermodynamics states that the entropy of a system approaches a constant value as the temperature approaches absolute zero. The entropy of a system at absolute zero is typically zero, and in all cases is determined only by the number of different ground states it has. Specifically, the entropy of a pure crystalline substance (perfect order) at absolute zero temperature is zero