1. A dry food product is contained in a 1 cm x 4 cm x 3 cm box using a polymer film to protect the oxygen sensitivity of the product. The concentration gradient across the film is defined by the oxygen concentration in air (0.01164 kg/m3) and 0.244 kg/m3 within the package. The oxygen diffusivity for the polymer film is 3 x 10-16 m2/s. Estimate a- the allowable flux of oxygen into the package (in kg O2/s), and b- the film thickness needed, to ensure a product shelf life of 10 months. The shelf life of the product is established as the time when oxidation reactions within the product have used 0.5 mol of oxygen.

What happens to energy in an open system?

Problem #3 (ch. 1, problem 15)the ideal gas law provides one way to estimate the pressure exerted by a gas on a container. the law isí‘ťí‘ť=푛푛푛푛푛푛푉푉more accurate estimates can be made with the van der waals equationí‘ťí‘ť=푛푛푛푛푛푛푉푉â’푛푛푟푟â’푞푞푛푛2푉푉2where the term nb is a correction for the volume of the molecules and the term an2/v2is a correction for molecular attractions. the values of a and b depend on the type of gas. the gas constant is r, the absolutetemperature is t, the gas volume is v, and the number of moles of gas molecules is indicated by n. if n = 1 mol of an ideal gas were confined to a volume of v = 22.41 l at a temperature of 0â°c (273.2k), it would exert a pressure of 1 atm. in these units, r = 0.0826.for chlorine gas (cl2), a = 6.49 and b = 0.0562. compare the pressure estimates given by the ideal gas law and the van der waals equation for 1 mol of cl2 in 22.41 l at 273.2 k. what is the main cause of the difference in the two pressure estimates, the molecular volume or the molecular attractions?

Aconcentrated solution of ammonia is 14.8m and has a density of 0.899g/l. what is the concentration of ammonia in this solution in weight percent (%w/w)?