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### Derive the Entropy changes for a reversible process

Let us consider entropy at the initial state 1 is S1 and entropy at the final state 2 is S2. Hence, the change in entropy of a system, as it undergoes a change from state 1 to 2, becomes S2 - S1 = 2∫1 (δQ / T) ...

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### Prove that Entropy is a Property

In order to prove that entropy is a property, we will suppose two cycles i.e. 1-A-2-B-1 and 1-A-2-C-1 as shown in For a reversible cycle 1-A-2-B-1: ∫1-A-2 δQ / T + ∫2-B-1 δQ / T = 0 For a reversible cycle 1-A-2-C-1: ∫1-A-2 δQ / T + ∫2-C-1 ...

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### What are Maxwell’s relationships?

The various relationships between internal energy (U), enthalpy (H), Helmholtz free energy (a) and Gibbs free energy (g), with relevant parameters such as entropy, pressure, temperature and volume are given by the following equations: 1. dU = TdS – PdV 2. dH = TdS + VdP 3. dA = - SdT ...

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### Explain the Entropy Principle?

Entropy Principle: Form the Clausius inequality, ∫ δQ / T ≤ 0 As the entropy is a property of the system, therefore the cyclic integral of a property is zero and the above equation can also be written as: ∫ δQ / T ≤ ∫ dS SQ / T ...

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### What is Entropy and what are its characteristics?

Entropy is a measure of the degree of randomness of the molecules comprising the system. Higher the disorder, greater is the increase in entropy. Entropy is the function of a quantity of heat which shows the possibility of conversion of that heat into work. The ...

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### Define Kelvin Planck and Clausius statements of the second law of Thermodynamics.

The second law of thermodynamics can also be stated using Clausius, Kelvin and Planck statements also. Each statement is based on an irreversible process. The Clausius and the Kelvin and Planck statements of the second law of Thermodynamics are given below: Clausius statement: Clausius statement states “it is ...

### A Carnot engine has the same efficiency (i) between 100 K and 500 K and (ii) between T K and 900 K. Calculate the temperature T of the sink.

Maximum efficiency of an engine working between temperatures T2 and T1 is given by the fraction of the heat absorbed by an engine which can be converted into work is known as efficiency of the heat engine. Mathematically, In First case: Efficiency, η = (T2 - T1) ...

### An ideal gas is heated from temperature T1 to temperature T2 by keeping its volume constant. The gas is expanded back to its initial temperature according to the law PVn = constant. If the entropy changes in the two processes are equal, find the value of n in terms of the adiabatic index γ

Change in entropy during constant volume process is given as: = m cv ln (T2 / T1) Change in entropy during polytropic process i.e. (PVn = constant) = m cv [(γ – n)/ (n – 1)] ln (T2 / T1) For the same entropy, equating both the above equations, ...

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