When I solve an exercise to calculate Gibbs Free Energs delta G I look in Tables and collect for Data for enthalpy and entropy and fill them in the formula deltaG = deltaH - T*deltaS. I am confused about the system and surrounding. Is this treated a open or closed System? Is it isothern .. I think y
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Nitrogen gas (molecular weight 28) is enclosed in a cylinder by a piston, at the initial condition of 2 bar, 298 K, and 1 m3. In a particular process, the gas slowly expands under isothermal conditions, until the volume becomes 2 m3. Heat exchange occurs with the atmosphere at 298 K during this proc
What's the method to solve this problem please? Air is throttled through a porous plug. The inlet conditions are 30 bar and 85°C and the outlet is 15 bar. The process is adiabatic and kinetic energies are negligible. Calculate the change in entropy per mass. Many thanks
An ideal gas of mass m and temperature T1 undergoes a reversible isothermal process from an initial pressure P1 to final pressure P2. The heat loss during the process is Q. The entropy changes ΔS of the gas is A. mR ln(P2/P1) B. mR ln(P1/P2) C. mR ln(P2/P1)−Q/T1 D. zero
One kg of an ideal gas (gas constant R=287J/kg-K) undergoes an irreversible process from state- I ( 1 bar, 300K ) to state-2 ( 2 bar, 300K). The change in specific entropy (s2−s1) of the gas (in J/kg.K) in the process is ____________ Answer: The change in entropy of the system is negative beca
Hi again, just wondering about this: "Air is compressed in a reversible polytrophic process (pv^n=constant) from an initial state of 15 bar and 100 ° to a final pressure of 50 bar. The polytropic exponent is n=1.3. Calculate the change in entropy per mass of air." Would we use p
Answer: Entropy is an abstract concept and is difficult to understand. To put it in simple words, "It is a degree of randomness of the system." Let's understand the meaning of it. Suppose we have a pure crystalline substance at 0 Kelvin. It has never seen heat. Never had its electrons gain any
A system undergoes a state change from 1 to 2. According to the second law of thermodynamics for the process to be feasible, the entropy change, S2-S1 of the system A. is positive or zero B. is negative or zero C. is zero D. can be positive, negative, or zero
An amount of 100 kW of heat is transferred through a wall in steady state. One side of the wall is maintained at 127 C and the other side at 27 C. The entropy generated (in W/K) due to the heat transfer through the wall is _____________
2 moles of oxygen are mixed adiabatically with another 2 moles of oxygen in the mixing chamber so that the final total pressure and temperature of the mixture become the same as those of the individual constituents at their initial states. The universal gas constant is given as R. The change in entr
Hello everybody, would somebody please put me on the right track to answering this question? 'Consider water undergoes a heat transfer at constant pressure of 10 MPa and changes from liquid to steam. Find the entropy of the system (sfg) as well as the heat transfer per unit mass in this process?'
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