Thermodynamics Q1

A fully charged battery gradually discharges while lying in a room at constant temperature. During discharging, it loses 1020 kJ to the environment. The battery is then recharged slowly to its initial state. The charging process consumes 0.7 kWh of electricity. What is the heat transfer during the charging process?

One kilogram of air is in a piston-cylinder apparatus that can only exchange heat with a reservoir at 300 K. Initially this air is at 100 kPa and 27°C. It is then compressed to 250 kPa and 27°C. The process is

Steam flows in a pipeline at 1.5 MPa where the enthalpy of saturated liquid and saturated vapor are 850 kJ/kg and 3000 kJ/kg. After expanding to 0.1 MPa in a throttling calorimeter, the enthalpy is found to be 2600 kJ/kg. The moisture content of steam (in percentage) in the pipeline is

A mass of 1 kg of air in a vessel expends from 4 bar, 77°C to 1 bar, 37°C while receiving 1.5 kJ of heat. The environment is at 0.95 bar, 27°C. The work done on the atmosphere is _________ kJ.

Two adiabatic chambers A and B, 2 m3 each are interconnected by a valve. Chamber A contains oxygen at 1000 kPa and 127°C and chamber B is evacuated. The valve is now opened until oxygen fills both the chambers and both chambers have the same pressure. The final pressure in the chambers is ____________ kPa.