But how? Before we are going to discuss second law, Do you know What is Entropy S? Entropy is the loss of energy to do work. So simply it is the unusable energy.

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But how? Before we are going to discuss second law, Do you know What is Entropy S? Entropy is the loss of energy to do work. So simply it is the unusable energy. As the usable energy consumed to do the work and converted into the unusable energy, then this unusable energy will gradually increase over time.

So the Second law states that the Entropy will be always increased or remains constant in a purely reversible process. It is not going to be decreased. The reversible process is not possible to build or it is an infinite process. Violation of Second law of thermodynamics As we said as the entropy increases on the earth then where this energy coming from?

So some critics claim that the evolution violates the second law of Thermodynamics. So this second Law is applied for the purely isolated or the closed system. But the earth is not an isolated or closed system since earth getting the energy from the sun. Various statements of the Second Law of Thermodynamics Along with the above statement, the second law of thermodynamics is expressed in many different ways.

Clausius statement: Heat cannot transfer from a low-temperature body to the high-temperature body until unless there is an external force on the system. This law is completely on the mathematical axiomatic foundation. In every neighbourhood of any state entropy S of an adiabatically enclosed system, there are states inaccessible from entropy S. Conclusion we have discussed the statement of the Second law and we have described the violations of the second law.

We do have different forms of statements for the second law and given the most prominent definitions. Please let us know your thoughts in the comment section below.


2nd Law of Thermodynamics

Though it does not explicitly say so, this statement refers to closed systems, and to internal energy U defined for bodies in states of thermodynamic equilibrium, which possess well-defined temperatures. That axiom stated that the internal energy of a phase in equilibrium is a function of state, that the sum of the internal energies of the phases is the total internal energy of the system, and that the value of the total internal energy of the system is changed by the amount of work done adiabatically on it, considering work as a form of energy. That article considered this statement to be an expression of the law of conservation of energy for such systems. This version is nowadays widely accepted as authoritative, but is stated in slightly varied ways by different authors. Such statements of the first law for closed systems assert the existence of internal energy as a function of state defined in terms of adiabatic work. Thus heat is not defined calorimetrically or as due to temperature difference. It is defined as a residual difference between change of internal energy and work done on the system, when that work does not account for the whole of the change of internal energy and the system is not adiabatically isolated.


Second law of thermodynamics

The first step is to convert the temperature to Kelvin, so add One must work backwards somewhat using the same equation from Example 1 for the free energy is given. Now all one has to do is to figure out the enthalpy of the reaction. The enthalpy is positive, because covalent bonds are broken.


Second Law of Thermodynamics

The term "thermodynamics" comes from two root words: "thermo," meaning heat, and "dynamic," meaning power. All things in the observable universe are affected by and obey the Laws of Thermodynamics. How so? Usable energy is inevitably used for productivity, growth and repair. In the process, usable energy is converted into unusable energy. Thus, usable energy is irretrievably lost in the form of unusable energy. As usable energy decreases and unusable energy increases, "entropy" increases.


What is the Second Law of Thermodynamics?

This statement introduces the impossibility of the reversion of evolution of the thermodynamic system in time and can be considered as a formulation of the second principle of thermodynamics — the formulation, which is, of course, equivalent to the formulation of the principle in terms of entropy. The second law allows[ how? These statements cast the law in general physical terms citing the impossibility of certain processes. The Clausius and the Kelvin statements have been shown to be equivalent. It refers to a cycle of a Carnot heat engine , fictively operated in the limiting mode of extreme slowness known as quasi-static, so that the heat and work transfers are between subsystems that are always in their own internal states of thermodynamic equilibrium. The Carnot engine is an idealized device of special interest to engineers who are concerned with the efficiency of heat engines. Interpreted in the light of the first law, it is physically equivalent to the second law of thermodynamics, and remains valid today.

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