9.Calculate the concentration of urea (NH2CONH2) that has an osmotic pressure of 30.0 atm at 25 °C.

Calculate the molality of a solution made by dissolving 115.0 g ethylene glycol, HOCH2CH2OH, in 500. mL water. The density of water at this temperature is 0.978 g/mL. Calculate the molarity of the solution.

The osmotic pressure of a solution containing 7.0 g of insulin per liter is 23 torr at 25 C. What is the molar mass of insulin?

6-111 As noted in Section 6-8C, the amount of external pressure that must be applied to a more concentrated solution to stop the passage of solvent molecules across a semipermeable membrane is known as the osmotic pressure The osmotic pressure obeys a law similar in form to the ideal gas law (discussed in Section 5-4), where Substituting for pressure and solving for osmotic pressures gives the following equation: RT MRT, where M is the concentration or molarity of the solution. (a) Determine the osmotic pressure at 25°C of a 0.0020 M sucrose (C12H22O11) solution. (b) Seawater contains 3.4 g of salts for every liter of solution. Assuming the solute consists entirely of NaCl (and complete dissociation of the NaCI salt), calculate the osmotic pressure of seawater at 25°C. (c) The average osmotic pressure of blood is 7.7 atm at 25°C. What concentration of glucose (C6H12O6) will be isotonic with blood? (d) Lysozyme is an enzyme that breaks bacterial cell walls. A solution containing 0.150 g of this enzyme in 210. mL of solution has an osmotic pressure of 0.953 torr at 25°C. What is the molar mass of lysozyme? (e) The osmotic pressure of an aqueous solution of a certain protein was measured in order to determine the protein's molar mass. The solution contained 3.50 mg of protein dissolved in sufficient water to form 5.00 mL of solution. The osmotic pressure of the solution at 25°C was found to be 1.54 torr. Calculate the molar mass of the protein.

The freezing point of a 0.21 m aqueous solution of H2SO4 is -0.796C. (a) What is i? (b) Is the solution made up primarily of (i) H2SO4 molecules only? (ii) H+ and HSO4- ions? (iii) 2H+ and 1SO42- ions?

Simple acids such as formic acid, HCOOH, and acetic acid, CH3COOH, are very soluble in water; however, fatty acids such as stearic acid, CH3(CH2)16COOH, and palmitic acid, CH3(CH2)14COOH, are water-insoluble. Based on what you know about the solubility of alcohols, explain the solubility of these organic acids.

Refer to Figure 13.10 ( Sec. 13-4b) to answer these questions. (a) Does a saturated solution occur when 65.0 g LiCl is present in 100 g H2O at 40 C? Explain your answer. (b) Consider a solution that contains 95.0 g LiCl in 100 g H2O at 40 C. Is the solution unsaturated, saturated, or supersaturated? Explain your answer. (c) Consider a solution that contains 50. g Li2SO4 in 200. g H2O at 50 C. Is this solution unsaturated, saturated, or supersaturated? Explain your answer. Figure 13.10 Solubility of ionic compounds versus temperature.

How do colloids differ from solutions with regard to dispersed particle size and homogeneity?

In a mountainous location, the boiling point of pure water is found to be 95C. How many grams of sodium chloride must be added to 1 kg of water to bring the boiling point back to 100C? Assume that i = 2.

The solubility of NaCl in water at 100 C is 39.1 g/100. g of water Calculate the boiling point of this solution. (Assume i = 1.85 for NaCl.)