Question 2 (Mass Transfer in Solids across Packaging): (a) Cellophane is being used to keep food moist at 38 C. Calculate the loss of water vapor in g/d at steady state for a wrapping 0.10 mm thick and an area of 0.200 m when the vapor pressure of water vapor inside is 10 mmHg and the air outside contains water vapor at a pressure of 5 mmHg. [8 Marks] Data given: The molar mass of water is 18.02 kg/kmol; 1 atm = 760 mmHg; and the permeability, PM, at 38 C is 1.82 x 10-10 m3 solute (STP)/(s m atm/m). (b) If the Cellophane is not found to properly prevent water loss from the food, what, arguably, are the four most important factors to consider when selecting another packaging material? [2 Marks]