Using the appropriate tables, determine the change in specific entropy between the specified states, in Btu/lb · °R.
oxygen as an ideal gas, T1 =
T2 = 520°R, p1 = 10 atm,
p2 = 5 atm.
Using the appropriate tables, determine the change in specific entropy between the specified states, in Btu/lb...
Thermodynamics COURSE Using the appropriate tables, determine the change in specific entropy between the specified states, in Btu/lb · °R. (a) water, p1 = 10 lbf/in.2, saturated vapor; p2 = 500 lbf/in.2, T2 = 1300°F. (b) ammonia, p1 = 140 lbf/in.2, T1 = 160°F; T2 = -10°F, h2 = 345 Btu/lb. (c) air as an ideal gas, T1 = 80°F, p1 = 1 atm; T2 = 340°F, p = 5 atm. (d) oxygen as an ideal gas, T1 = T2...
Calculate the change in entropy ΔS for 5.2 moles of an ideal gas when its thermodynamic state changes from p1 = 1.50 atm and T1 = 400.0 K to p2 = 3.00 atm and T2 = 600.0 K. The molar heat capacity of the gas at constant volume is CV,m = (7/2) R, and is independent of the temperature.
At steady state, 1.8 lb/s of hot gaseous products of combustion cool from p1 = 18.0 lbf/in2, T1 = 2400°F to p2 = 16.0 lbf/in2, T2 = 260°F as they flow through a pipe. Heat transfer from the gas occurs at a boundary temperature of Tb = 230°F. Use the ideal gas model with Cp = 0.25 Btu/lb.°R and an average molecular weight, M = 27.5 lb/lbmol. Let To = 60°F and ignore the effects of motion and gravity. Determine...
1. Using the tables for water, determine the specific entropy at the indicated states, in kJ/kg.K. In each case, locate the state by hand on a sketch of the T-s diagram a. p-5.0 MPa, T-4000 b. p 5.0 MPa, T 100o c. p 5.0 MPa, u-1872.5 kJ/kg d. p 5.0 MPa, saturated vapor.
1. Using the tables for water, determine the specific entropy at the indicated states, in kJ/kg.K. In each case, locate the state by hand on a sketch...
5. Hydrogen undergoes a polytropic process with n=0.7 from an initial specific volume of 22 ft3/lb and initial temperature of 200° F to a final specific volume of 16 ft3/lb. The entropy decrease during the process is 7.5 Btu/°R. Model the hydrogen as an ideal gas with constant specific heats. Evaluate the specific heat at 200° F. Determine the mass of the hydrogen.
3. Air is heated from 5400 R to 12000 R while the pressure drops from 50 lbf/in2 to 40 lbf/in2, assuming constant specific heat (Cp 0.24 Btu/lbm-R) and R 53.33 Btu/lbm-R (a) Determine the change of entropy per pound of air (b) If the air was cooled from 1200° R to 540° R while the pressure drops from 50 lbf/in2 to 40lbf/in2 what does it say about the system entropy? Does the result violate the entropy increase principle?
3. Air...
Air behaving like an ideal gas contained in a piston–cylinder assembly undergoes an isothermal process between end states, 1 and 2, where P1 = 10 bar, V1 = 0.1 m3, T1 = 300 K and P2 = 1 bar, V2 = 1 m3, T2 = 300 K. The work done by the process is:
5. Calculate the change in entropy of an ideal gas when 2.00 moles of it is changed from 25 °C and 1.50 atm to 135 °C and 7.00 atm. You may assume that Cp.m=5/2 R. (10 pts) J/K
True or False (Problems 1 through 10) 1. The change in entropy of a closed system is the same for every process between two specified states 2. The entropy of a fixed amount of an incompressible substance increases in every process for which temperature increases 3. A process that violates the second law of thermodynamics violates the first law of thermodynamics. 4. When a net amount of work is done on a closed system undergoing an internally reversible process, a...
Using the tables for water, determine the specified property data at the indicated states. (a) At p = 3 bar, v = 0.35 m3/kg, find T in °C and u in kJ/kg. (b) At T = 320°C, v = 0.33 m3/kg, find p in MPa and u in kJ/kg. (c) At p = 28 MPa, T = 400°C, find v in m3/kg and h in kJ/kg. (d) At T = 10°C, v = 70 m3/kg, find p in kPa and...