A30l digester bioreactor is charged with media and 3.75l of cow dung. the reactor produces 5l of biogas per one liter of cow dung at a pressure of 1 atm and a temperature of 27oc. the biogas leaving the digester is saturated with water. on a dry basis, this gas contains 80 mol% methane and 20 mol% carbon dioxide. the gas is then fed to a furnace with 7 mols of dry air and undergoes complete combustion and complete conversion. determine the composition of the resulting gas.

A2-m rigid tank initially contains saturated water vapor at 100 kpa. the tank is connected to a supply line through a valve. steam is flowing in the supply line at 600 kpa and 300 c. the valve is opened, and steam is allowed to enter the tank until the pressure in the tank reaches the line pressure, at which point the valve is closed. a thermometer placed in the tank indicates that the temperature at the final state is 200°c. determine (a) the mass of steam that has entered the tank (b) the amount of heat transfer.