Acrylic resins are polymeric materials used to make warm yet lightweight garments. The osmotic pressure of a solution prepared by dissolving 47.7 g of an acrylic resin in enough water to make 500. mL of solution is 0.325 atm at 25°C.

(a) What is the average molar mass of the polymer?

(b) How many monomers constitute the “average” molecule? The repeating unit of this acrylic resin has the formula —CH₂CH(CN)—.

(c) What would be the vapor pressure of the solution given that the vapor pressure of pure water at 25°C is 0.0313 atm? (Assume that the density of the solution is 1.00 g · cm^–3.)

(d) Which approach (osmometry or the lowering of vapor pressure) would you prefer for the determination of very high molar masses such as those of acrylic resins? Why?