Hydrogen gas (density = 1.165 kg/m^3 ) is stored at 25°C in a permeable cylindrical container which has an outer diameter of 0.25 m, a wall thickness of 5 mm and a length of 2 m. The cylinder is exposed to ambient air.
If the container is charged to an initial pressure of 5 bars, at what would be the mass diffusion rate (in kg/s) of hydrogen through the cylinder? Hydrogen solubility in the container is 0.5X10^(-3) kmol/m^3 bar and diffusivity at 293K and 1 bar is 0.4x10^(-13) m^2 /s.

Apiston-cylinder with a volume of 0.25 m3 holds 1 kg of air (r 0.287 k/kgk) at a temperature of 100 c. heat transfer to the cylinder causes an isothermal expansion of the piston until the volume triples. how much heat is added to the piston-cylinder?

Water at 70°f and streams enter the mixing chamber at the same mass flow rate, determine the temperature and the quality of the exiting stream. 0 psia is heated in a chamber by mixing it with saturated water vapor at 20 psia. if both streams enters the mixing chamber at the same mass flow rate, determine the temperature and the quality of the existing system.

For the closed feedwater heater below, feedwater enters state 3 at a pressure of 2000 psia and temperature of 420 °f at a rate of ix10 ibhr. the feedwat extracted steam enters state 1 at a pressure of 1000 psia and enthalpy of 1500 btu/lbm. the extracted er leaves at an enthalpy of 528.7 btu/lbm steam leaves as a saturated liquid. (16) a) determine the mass flow rate of the extraction steam used to heat the feedwater (10) b) determine the terminal temperature difference of the closed feedwater heater