Chapter 6, Problem 6.54P

Carbon dioxide (CO₂) fills a closed, rigid tank fitted with a paddle wheel, initially at 80°F, 20 lb/in², and a volume of 1.8 ft³. The gas is stirred until its temperature is 500°F. During this process heat transfer from the gas to its surroundings occurs in an amount 2.6 Btu. Assume ideal gas behavior, but do not assume constant specific heats. Kinetic and potential energy effects can be ignored. Determine the mass of the carbon dioxide, in lb, and the work, in Btu. Step 1 Determine the mass of the carbon dioxide, in lb. m = i Save for Later lb Attempts: 0 of 4 used Submit Answer Step 2 The parts of this question must be completed in order. This part will be available when you complete the part above.

Air expands steadily through a turbine from 6 bar, 800 K to 1 bar, 520 K. During the expan sion, heat transfer from air to the surroundings at 300 K is 10 kJ/kg air. Neglect the changes in kinetic and potential energies and evaluate the irreversibility per kg air. Assume air to behave as an ideal gas with Cp = 1.0 kJ/(kg.K) and R = 0.3 kJ/(kg.K) %3D

for steam, the specific ideal gas constant = 461.5 J/kg K A closed system is comprised of pure water substance initially at a temperature of 500 oC and a pressure of 20 MPa (state 1). The system undergoes an isochoric process whereby its pressure drops to 0.1 Mpa (state 2). Evaluate the specific entropy, specific volume and temperature of the system at state 2.

Carbon dioxide (CO₂) fills a closed, rigid tank fitted with a paddle wheel, initially at 80°F, 50 lb/in², and a volume of 1.6 ft³. The gas is stirred until its temperature is 500°F. During this process heat transfer from the gas to its surroundings occurs in an amount 2.6 Btu. Assume ideal gas behavior, but do not assume constant specific heats. Kinetic and potential energy effects can be ignored. Determine the mass of the carbon dioxide, in lb, and the work, in Btu.

Carbon dioxide (CO₂) fills a closed, rigid tank fitted with a paddle wheel, initially at 80°F, 50 lb/in², and a volume of 1.6 ft³. The gas is stirred until its temperature is 500°F. During this process heat transfer from the gas to its surroundings occurs in an amount 2.6 Btu. Assume ideal gas behavior, but do not assume constant specific heats. Kinetic and potential energy effects can be ignored. Determine the mass of the carbon dioxide, in lb, and the work, in Btu. Step 1 Determine the mass of the carbon dioxide, in lb. m = 0.60792 Hint Your answer is correct. Step 2 * Your answer is incorrect. Determine the work, in Btu. W12= -53.4318 eTextbook and Media Hint lb Btu Attempts: 1 of 4 used Assistance Used

Refrigerant 134a enters an insulated compressor operating at steady state as saturated vapor at -26°C with a volumetric flow rate of 0.18 m3/s. Refrigerant exits at 7 bar, 70°C. Changes in kinetic and potential energy from inlet to exit can be ignored. 1.Determine the volumetric flow rate at the exit, in m3/s 2. Determine the compressor power, in kW.

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23 m³/hr of air at 600 kPa, 330 K enters a well-insulated, horizontal pipe having a diameter of 1.2 cm and exits at 120 kPa. Assume steady state and use the ideal gas model for the air. Also assume constant specific heat, c = 1.007 kJ/kg-K for air at 330K. Determine the mass flow rate, in kg/s, and the exit velocity, in m/s. Step 1 Determine the mass flow rate, in kg/s. m₁ = 0.04047 kg/s Step 2 Determine the exit velocity, in m/s. V₂ = 178.315 x m/s