Question

1.) A protein solution containing 70.0 mg of the protein (dissolved in water) displays an osmotic pressure of 319.88 Pa at 310.15 K. If the volume of the protein solution is 20.0 mL, what is the molar mass of the protein?

2.) Calculate the osmotic pressure at 15°C of a solution of naphthalene (C₁₀H₈) in benzene containing 0.228 mol naphthalene per liter of solution.

3.) A solution of potassium chloride (KCl) is prepared by dissolving 9.63 g of the salt in 1.00 kg water (H₂O). What is the freezing point of this solution? (The freezing point of pure water is 0°C (exactly) at 1 atm pressure; the molal freezing-point-depression constant for water is 1.86°C/m.)