Question

1.Argon contained in a closed, rigid tank, initially at 62.3°C, 3.9 bar, and a volume of 4.2 m³, is heated to a final pressure of 9.4 bar. Assuming the ideal gas model with k = 1.6 for the argon, determine the heat transfer, in kJ.

2.Water vapor contained in a piston–cylinder assembly undergoes an isothermal expansion at 223°C from a pressure of 5.4 bar to a pressure of 1.9 bar. Evaluate the work, in kJ/kg.

3.A mass of 4 kilograms of carbon dioxide (CO₂) in a piston-cylinder assembly undergoes two processes in series from an initial state where p₁ = 2.1 MPa, T₁ = 282°C:

Process 1–2: Constant-temperature expansion until the volume is twice the initial volume.

Process 2–3: Constant-volume heating until the pressure is again 2.1 MPa.

Assuming ideal gas behavior, determine the overall work, in kJ.

4.

Nitrogen (N₂) contained in a piston–cylinder arrangement, initially at 5.4 bar and 420 K, undergoes an expansion to a final temperature of 300 K, during which the pressure–volume relationship is pV^1.5 = constant. Assuming the ideal gas model for the N₂, determine the heat transfer in kJ/kg.

5.A piston–cylinder assembly contains air, initially at 2.1 bar, 152 K, and a volume of 1.2 m³. The air undergoes a process to a state where the pressure is 0.9 bar, during which the pressure–volume relationship ispV = constant. Assuming ideal gas behavior for the air, determine the mass in kg.

Answer 1