Refrigerant 134a (R134a) is at vapor/liquid equilibrium at 300 K. The saturation pressure is 7.0282 bar, the entropy of the saturated liquid is 1.1287 J/(g K) and the entropy of the saturated vapor is 1.7156 J/(g K). If the system has a an entropy of 1.38 J/(g K), what is the quality? (That is, what fraction of the system is vapor?) Report your answer to three decimal places.

Nitrogen flows into a throttling valve with a volume flow rate of 2 cm3/min at 250 bar and 250 K. The nitrogentemperature after throttling is 240 K. Determine the mass flow rate of nitrogen and the pressure after throttling. Inclue pv and ts diagrams.

1 x 10 ° mm3 of air at a pressure of 10 bar and temperature 300°C, expands 10 times its original volume and its final temperature will be 25°C. Calculate (1) mass (ii) change in entropy by considering temperature, volume, entropy relationship (iii) change in entropy by considering temperature, pressure, entropy relationship (iii) change in entropy by considering pressure, volume, entropy relationship. Gas Molecular weight (M) (kJ/kg K) (kJ/kg K) Air 28.97 1.005 0.718 Oxygen Nitrogen Hydrogen Carbon monoxide 32 0.920 0.660 28 1.046 0.754 14.40 10.40 28 1.046 0.754