Question

QUESTION 4 12.5 points Save Answer Carbon Oxide (CO) initially occupying 2 m at 7.4 bar, 246.85°C undergoes an internally reversible expansion during which pv 1.5 = constant to a final state where the temperature is 36.85°C. Assuming the ideal gas model, determine: a) The entropy change, in Joules/K. QUESTIONS b) The pressure at the final state (bar). 12.5 points Save Answe

Answer 1

Polytropic Process: Initial volume v1 = 2 m3 Pressure P1 = 7.4 bar = 7.4 x 105 Pa Temperature T1 = 246.85°C = 519.85 K expansion law pv 1.3 = C Final Temperature T2 = 36.85 °C Entropy change for Polytropic process 95 = c, n (%) +R 19

Assuming carbon oxide (CO) Cp = 1.02 kJ/kg K, Cy = 0.72 kJ/kg K R = 0.297 kJ/kg K AS = 0.72 x 103 in (509:85) + 0.297 x 103 ( 1.3 – 1) in (509.85) AS = 372.565 – 512.277 AS = -184.712 1/K