Mean temperature of the mixture = (T1 + T2) / 2
Thus change in entropy is given by:
∆S = S2 - S1)
= mc (T1 + T2)/2∫ T1 (dT / T) – mc T2∫ T1 + T2)/2 (dT / T)
= mc ln (T1 + T2)/2 ...

ContinueComments Off on A mass ‘m’ of fluid at temperature T_{1} is mixed with an equal amount of the same fluid at temperature T_{2}. Prove that the resultant change of entropy of the universe is: [2 mc ln (T_{1} + T_{2}) / 2]/[(T_{1} T_{2})^{1/2}]and also prove that it is always positive.

Gibbs-Duhem Equation
The Gibbs free energy can be defined in two different ways once by subtracting off combinations of entropy S, enthalpy H and temperature T and other as a sum of chemical potentials and amounts of species. The fact that they are equal gives a ...

Clapeyron discovered an important fundamental equation which helps in finding the extensive application in one component, two phase system and by Clausius from second law of thermodynamics. Hence this fundamental equation is known as Clapeyron-Clausius Equation. One of the uses of this equation is to ...

We know that cyclic is given as:
(∂P / ∂V)S (∂V / ∂S)P (∂S / ∂P)V = -1
(∂P / ∂V)S = - [(∂S / ∂V) P]/[(∂S / ∂P)V] = [- (∂S / ∂T)P (∂T / ∂V)P]/[(∂S / ∂T) V (∂T / ∂P)V]
= -[ (CP / T) ...

ContinueComments Off on Using an appropriate cyclic rule and an appropriate Maxwell relation, show that (∂P / ∂V)_{S} = γ (∂P / ∂V)_{T } where γ = C_{P / CV}

ContinueComments Off on Three real heat engines have the same thermal efficiency and are connected in series. The first engine absorbs 2400 kJ of heat from a thermal reservoir at 1250 K and the third engine ejects its waste of 300 kJ to a sink at 150 K. determine the work output from each engine.

Lewis introduced a concept by making use of free energy function G to represent the actual behavior of real gases which is very much different from the concept of ideal gases. This concept is known as concept of Fugacity.
We know that the variation of free ...

ContinueComments Off on Explain the concept of Fugacity?

The variation of free energy change with change in temperature and pressure is discussed below:
Consider the following equation:
G = H – TS …………………………………….……. (1)
As H = U + PV
Substituting the value of H in equation (1) we will get:
G = U + PV – TS ...

ContinueComments Off on Discuss the variation of free energy change with Temperature and Pressure.

Physical Significance of Entropy:
1. Entropy as a measure of the Disorder of the system:
We know that all the spontaneous process in which heat is transferred through a finite temperature. Spontaneous process is also known as irreversible process because these processes take place at very fast ...