Each molecule in a gas has some kinetic energy. What is the total kinetic energy of all the molecules in 3.21 mol of a gas whose temperature is 373 K? Number n Units v The diffusion constant of ethanol in water is 12.4 x 10'10 m2/s. A cylinder has a crosssectional area of 5.32 cm2 and a length of 2.22 cm. A difference in ethanol concentration of 1.29 kg/m3 is maintained between the ends of the cylinder. In 62.2 minutes, what mass of ethanol diffuses through the cylinder? Number I Units v An apartment has a living room whose dimensions are 2.4 m x 5.1 m x 6.2 m. Assume that the air in the room is composed of 79% nitrogen {N2} and 21% oxygen (02}. At a temperature of 21 CC and a pressure of 1.01 x 105 Pa. what is the mass (in grams) of the air? Number n Units v