Question

Using the regular solution model, show that oil and water do not mix unless the solution is very dilute. Assume oil is the solute. For hydrocarbon-water mixtures assume w-5 and T-300K. Do oil and water mix if x_av- 0.3? Calculate Delta G_MIX. Is it positive, negative, or zero? How about if x_mi = 0.0001? Do oil and water mix at this concentration of oil? At what mole fraction is the oil in equilibrium with its dissolved form? To solve this problem plot Delta G_Mix as a function of x_w. for values of X_y between 0.3 and 0.0001. Determine from the graph the mole fraction where Delta G_mix=0. In the prior problem set we used the regular solution model to show that oil and water do not mix unless the solution is very dilute. But regular solution theory is not the best model to use for such a calculation because oil and water do not have similar molecular volumes. Assume oil is a hydrocarbon polymer for which N=10 and is the solute. For hydrocarbon-watch mixtures assume wsp=5 and T=300K. Calculate Delta G_Mx. Delta H_Mix, Delta S_Mix if = 0.3. Does oil dissolve in water under these conditions? Repeat the calculations in part a for =0.0001? Do oil and water mix at this concentration of oil? Explain any differences with the results obtained in the last problem set using regular solution theory. Repeat the calculations in parts a and b but now assume wsr=l. Explain any differences between these results and the results of parts a and B The following table gives the osmotic pressure of aqueous solutions of bovine serum albumin (BSA) as a function mass concentration w2: Assuming that this solution docs NOT behave ideally, determine from an appropriate graph of these data the molecular weight of BSA.

Answer 1