Chapter 6, Problem 6.40CU

This question requires the use of the Thermodynamic Property Tables supplied as additional material.In addition, for steam, the specific ideal gas constant = 461.5 J/kg KA closed system is comprised of pure water substance initially at a temperature of 500 C and a pressure of 20 MPa (state 1).The system undergoes an isochoric process whereby its pressure drops to 0.1 Mpa (state 2).(a) Evaluate the specific entropy and specific volume of the system at state 1.(b) Evaluate the specific entropy, specific volume and temperature of the system at state 2.(c) Sketch the process on a Temperature-specific entropy plot, showing the lines of constant pressure which pass through steps 1 and 2.(d) For state 1 evaluate the specific volume assuming the steam behaves as an ideal gas and comment on your result.

DESCRIBE THE ENTROPY CHANGE OF PURE SUBSTANCES?

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Establish the increase of entropy principle.

Three-tenths kmol of carbon monoxide (CO) in a piston– cylinder assembly undergoes a process from p1 = 150 kPa, T1 = 300 K to p2 = 500 kPa, T2 = 420 K. For the process, W = -300 kJ.Employing the ideal gas model, determine:(a) the heat transfer, in kJ.(b) the change in entropy, in kJ/K.

Two moles of a diatomic ideal gas such as oxygen are compressed adiabatically and reversibly from an initial state (1.96 atm, 19.11 L) to a final state with a pressure of 7.5 atm. Assume that Cv=5R Determine the change in the internal energy of the gas in this process (in J). 4,756.2334 margin of error +/- 1%

The state of an ideal gas with C_P = (5/2)R is changed from P1 = 1 bar and V1=12 m3 to P2​=12 bar and V2=1 m3 by the following mechanically reversible processes: (a) Isothermal compression. (b) Adiabatic compression followed by cooling at constant pressure. (c) Adiabatic compression followed by cooling at constant volume. (d) Heating at constant volume followed by cooling at constant pressure. (e) Cooling at constant pressure followed by heating at constant volume. Calculate Q, W, ΔU, and ΔH for each of these processes, and sketch the paths of all processes on a single PV diagram.

n moles of air are contained in a closed system at a temperature of 300 K, pressure of 1.5 bar and volume of 0.015 m. This system undergoes a thermodynamic cycle consisting of the following three reversible processes in series: (i) isothermal compression to a pressure of 5 bar, (ii) constant pressure heating, and (iii) constant volume cooling to the initial state. Assuming the air behaves ideally, and taking Cp = 20.8 J mol-K-1 and C, = 12.5 J mol-1K-1: (a) Draw this cycle on a P-V diagram, labelling the isotherms and states. (b) Calculate T3, the temperature at the end of the isobaric heating (K). (c) Calculate the total work done by the entire cycle, W (J).

6. A certain quantity of gas occupies 0.56 m³ at 400° C and 28 bar. Determine the gain in entropy if the gas expands isothermally to a final volume of 2.8 m². R= 287 J/kg K. the following creas Ans. 3.746 kJ/KI