If the turbine is reversible, how much work is produced per kg of steam?

Steam is fed to an adiabatic turbine at 4 MPa and 500°C. It exits at 0.1 MPa.

(a) If the turbine is reversible, how much work is produced per kg of steam?

(b) If the turbine is 80% efficient, how much work is produced per kg of steam? .

Methane is compressed in a steady-state adiabatic compressor (87% efficient) to 0.4 MPa. What is the required work per mole of methane in kJ? If the flow is to be 17.5 kmol/h, how much work must be furnished by the compressor (in kW)? What is the rate of entropy generation (in kJ/K/h)? (a) the inlet is at 0.1013 MPa and 240F; (b) the inlet is 0.1013 MPa and 200 K.