Derive Entropy of a mixture of Ideal Gases
admin For one mole of an ideal gas: dS = Cv dT / T + R dV / V Integrating the above equation, assuming that Cv remains constant for an ideal…
April 2025
An iron cube at a temperature of 400o C is dropped into an insulated bath containing 10kg water at 25o C. the water finally reaches a temperature of 50o C at steady state. Given that the specific heat of water is equal to 4186 J / kg K. find the entropy changes for the iron cube and the water. Is the process reversible? If so why?
Given: temperature of the iron cube = 400o C = 400 + 273 = 673 K Temperature of water = 10 kg Temperature of water and cube after equilibrium =…
What is the Physical Significance of Entropy?
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…
Discuss the variation of free energy change with Temperature and Pressure.
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…
Explain the concept of Fugacity?
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…
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.
Data given: Q1 = 2400 KJ Q4 = 300 KJ For engine E1, Efficiency η1 = (Q1 – Q2) / Q1 = 1 – (Q2 / Q1) I.e. Q2 /…
Using an appropriate cyclic rule and an appropriate Maxwell relation, show that (∂P / ∂V)S = γ (∂P / ∂V)T where γ = CP / CV
We know that cyclic is given as: (∂P / ∂V)S (∂V / ∂S)P (∂S / ∂P)V = -1 (∂P / ∂V)S = – / = / = -/ = –…
Explain Clapeyron-Clausius Equation and also give its derivation
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…
Derive the Gibbs-Duhem Equation and give its Applications?
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…
A mass ‘m’ of fluid at temperature T1 is mixed with an equal amount of the same fluid at temperature T2. Prove that the resultant change of entropy of the universe is: [2 mc ln (T1 + T2) / 2]/[(T1 T2)1/2]and also prove that it is always positive.
Mean temperature of the mixture = (T1 + T2) / 2 Thus change in entropy is given by: ∆S = S2 – S1) = mc (T1 + T2)/2∫ T1 (dT…