3. Courtesy of Alzet Osmotic Pumps Pharmaceutics  Cancer Treatments  Painkillers Agriculture  Fertilization of crops Fragrances  Air freshener  Bug repellant

4. #1: Semi-permeable membranes and controlled concentrations can create a zero-order rate of diffusion. #2: Polar membranes diffuse polar substances like alcohols at a zero- order rate.

5. J = mass flux D = diffusion co- efficient dC = C IN - C OUT dX = thickness of membrane

6. (Ra) 2 = 4(δ D1 -δ D2 ) 2 + (δ P1 -δ P2 ) 2 + (δ H1 - δ H2 ) 2 RED = Ra/Ro δ D = London dispersion forces δ P = Dipole-dipole interactions δ H = Hydrogen bonding Ra = Solubility difference Ro = Solubility radius RED = Relative energy difference

11. Courtesy of Vernier Software & Technology

12. Citric AcidAscorbic Acid Acetylsalicylic Acid 147.76 g/100 mL33.O g/100 mL0.30 g/100 mL