When 15,0 g of ethyl alcohol (C2H5OH) is dissolved in 750 g of formic acid, the freezing point of the solution is 7,2 C. Freezing point of pure formic acid 8,4 C. Calculate the Kd value of formic acid. (ethyl alcohol: 46 g/mol)

A compound has a solubility in water of 250 mg/L at 25C. Should this compound be characterized as a soluble or insoluble compound at 25C?

For each of the following pairs of solutions, select the solution for which solute solubility is greatest. a. Oxygen gas in water with P = 1 atm and T = 10C Oxygen gas in water with P = 1 atm and T = 20C b. Nitrogen gas in water with P = 2 atm and T = 50C Nitrogen gas in water with P = 1 atm and T = 70C c. Table salt in water with P = 1 atm and T = 40C Table salt in water with P = 1 atm and T = 70C d. Table sugar in water with P = 3 atm and T = 30C Table sugar in water with P = 1 atm and T = 80C

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.

The freezing point of p-dichlorobenzene is 53.1 C, and its Kf is 7.10 C kg/mol. A solution of 1.52 g of the drug sulfanilamide in 10.0 g p-dichlorobenzene freezes at 46.7 C. Calculate the molar mass of sulfanilamide.

Some lithium chloride, LiCl, is dissolved in 100 mL of water in one beaker, and some Li2SO4 is dissolved in 100 mL of water in another beaker. Both are at 10 C, and both are saturated solutions; some solid remains undissolved in each beaker. Describe what you would observe as the temperature is raised. The following data are available to you from a handbook of chemistry:

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?

Butane, C4H10, has been suggested as the refrigerant in household compressors such as those found in air conditioners. (a) To what extent is butane soluble in water? Calculate the butane concentration in water if the pressure of the gas is 0.21 atm. (kH = 0.0011 mol/kgbar at 25 C) (b) If the pressure of butane is increased to 1.0 atm, does the butane concentration increase or decrease?

A sample of aluminum sulfate 18-hydrate, Al2(SO4)3. 18H2O, containing 125.0 mg is dissolved in 1.000 L of solution. Calculate the following for the solution: a The molarity of Al2(SO4)3. b The molarity of SO42. c The molality of Al2(SO4)3, assuming that the density of the solution is 1.00 g/mL.

A sample of potassium aluminum sulfate 12-hydrate. KAl(SO4)212H2O, containing 101.5 mg is dissolved in 1.000 L of solution Calculate the following for the solution: a The molarity of KAl(SO4)2. b The molarity of SO42. c The molality of KAl(SO4)2, assuming that the density of the solution is 1.00 g/mL