In which system entropy is zero?
Example: In the Adiabatic process no exchange of heat and mass transfer is possible and therefore, the entropy of the system is zero.
If there is no difference in the final and initial state of entropy then entropy will be zero. Devices with a steady state of flow of energy like nozzles, and turbines have zero entropy. Reversible processes also have zero entropy.
Specifically, the entropy of a pure crystalline substance (perfect order) at absolute zero temperature is zero.
Therefore, the entropy change of a system is zero if the state of the system does not change during the process. For example entropy change of steady flow devices such as nozzles, compressors, turbines, pumps, and heat exchangers is zero during steady operation.
The entropy of a pure state is zero because there is no uncertainty in this state (in line with the Copenhagen interpretation of QM).
Entropy change in reversible adiabatic expansion of an ideal gas is zero.
Entropy is the number of possible configurations of a system; at zero temperature, this is equal to the number of lowest-energy states of the system. By the above, there are many such possible states (any given sample of gas adopts only one at a time), so the entropy is nonzero.
|Main Story||48||2h 56m|
|Main + Extras||10||3h 46m|
|All PlayStyles||68||3h 30m|
Thus, Entropy change during reversible adiabatic expansion is always zero.
For the irreversible process (for example, diffusion of solute from high concentrated region to lower concentrated region), the system does not return to the original state. Therefore, the net change in the entropy is always non zero or they increase the entropy of the system.
At which condition will the entropy of a pure solid be zero?
Solution : At 0 K , there is a perfectly ordered arrangement of the constituent particle of a pure crystalline substance and there is no disorder at all. Hence,its entropy is taken an zero. This statement is based on the third law of thermodynamics.
In general, the steady-state error will be zero if there is at least one pure integrator in the forward path of a unity feedback control system with a step input, but a different form of input will give an error.
At equilibrium as the system will be reversible so the total change in entropy will be zero.
In a steady state process, the entropy of the universe increases with time, the state of the substance inside the control volume changes as it is moved from one spatial location to the other, and the rate for the change in state is constant with time.
Only a perfectly ordered, crystalline substance at absolute zero would exhibit no molecular motion and have zero entropy.
A state is called pure if it cannot be represented as a mixture (convex combination) of other states, i.e., if it is an extreme point of the convex set of states. This is equivalent to the density matrix being a one dimensional projector, i.e., of the form ρ = |ψ⟩⟨ψ| for some unit vector |ψ⟩.
The zeroth law states that if two thermodynamic systems are in thermal equilibrium with each other, and also separately in thermal equilibrium with a third system, then the three systems are in thermal equilibrium with each other.
If the entropy of a system is zero, this means that the system is in perfect order and that the particles are all in a stationary state. This only happens at absolute zero temperature.
For a Carnot cycle the entropy change is zero: A S = 0. This is certainly true for the engine because it returns to its initial state after 1 cycle, and entropy is solely a function of the state. During the 2 adiabatic parts of the Carnot cycle, Q = 0, so A S = 0 during the adiabatic processes.
The entropy change in an adiabatic process is zero.
For which process is ΔS process 0?
19.4: Criteria for Spontaneous Change: The Second Law of Thermodynamics.
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In a adiabatic process there is no external pressure for the gas to expand against, the work done by or on the system is zero. Since this process does not involve any heat transfer or work, the first law of thermodynamics then implies that the net internal energy change of the system is zero.
In the reversible case, the change in entropy of the surroundings is equal and opposite to the change in the system, so the change in entropy of the universe is zero.