Determine the mass flux of benzene through a layer of air 10mm thick at 25°C and 200 kN/m² total pressure. The partial pressure of benzene is 6 kN/m2 at the left side of the layer and 1 kN/m2 at the right side. The mass diffusivity at this temperature and pressure is 4.4x10-6 m2/s

Estimate the thermal conductivity of benzene at 30C.

When two objects at different temperatures are brought into contact with one another (such as a hot steel bar dropped into cold water), the cold object will O increase in temperature to the same temperature as the hot object before being placed in the water. O lose as much heat as the hot object loses the cold object will remain unchanged O gain as much heat as the hot object loses

A piece of beef steak 7 cm thick will be frozen in the freezer room -30 ° C. This product has a moisture content of 73%, a density of 970 kg / m³, and a thermal conductivity (frozen) of 1.1 W / (m K). Estimate the freezing time. using the Plank equation. This product has an initial freezing temperature of -1.75 ° C, and the movement of air in the freezing room gives a convective heat transfer coefficient of 15 W / (m² K). t f = ... hour.