SOLVED

11) Determine DHsolute for KBr if the DHsolution (KBr) = +19.9 kJ/mol and the ΔHhydration(KBr) = -670. kJ/mol. A) +650 kJ/mol B) -650 kJ/mol C) +690 kJ/mol D) -710 kJ/mol E) -690 kJ/mol 12) A solution containing less than the equilibrium amount is called A) an unsaturated solution. B) a dilute solution. C) a supersaturated solution. D) a concentrated solution. E) a saturated solution. 13) A solution containing more than the equilibrium amount is called A) an unsaturated solution. B) a dilute solution. C) a supersaturated solution. D) a concentrated solution. E) a saturated solution. 14) A solution is formed at room temperature by vigorously dissolving enough of the solid solute so that some solid remains at the bottom of the solution. Which statement below is true? A) The solution is considered unsaturated. B) The solution is considered supersaturated. C) The solution is considered saturated. D) The solution would be considered unsaturated if it were cooled a bit to increase the solubility of the solid. E) None of the above are true. 15) Which of the following statements is generally true? A) The solubility of a solid is not dependent on either temperature or pressure. B) The solubility of a solid is highly dependent on pressure. C) The solubility of a solid is highly dependent on both pressure and temperature. D) The solubility of a solid is highly dependent on temperature. E) None of the above. 16) A solid can be purified through what technique? A) recrystallization B) dilution C) dissolution D) boiling E) melting 17) Which of the following statements is true? A) In general, the solubility of a solid in water decreases with increasing temperature. B) In general, the solubility of a gas in water decreases with increasing temperature. C) The solubility of a gas in water usually increases with decreasing pressure. D) The solubility of an ionic solid in water decreases with increasing temperature. E) None of the above statements are true. 18) Determine the Henry’s law constant for ammonia in water at 25°C if an ammonia pressure of 0.022 atm produces a solution with a concentration of 1.3 M. A) 59 M/atm B) 0.017 M/atm C) 0.029 M/atm D) 35 M/atm E) 0.038 M/atm 19) A sealed container contains 0.352 L of water with an atmosphere of oxygen gas. What is the concentration of O2 in the water if the external pressure is 4.24 atm given that kH for O2 is 1.66 × 10-6 M/mm Hg at this temperature? A) 5.34 × 10-3 M B) 1.53 × 10-3 M C) 9.46 × 10-2 M D) 5.34 × 10-2 M E) 3.82 × 10-4 M 20) Calculate the mass of oxygen (in mg) dissolved in a 5.00 L bucket of water exposed to a pressure of 1.13 atm of air. Assume the mole fraction of oxygen in air to be 0.21 given that kH for O2 is 1.3 × 10-3 M/ atm at this temperature. A) 49.4 mg B) 23.5 mg C) 9.87 mg D) 27.3 mg E) 13.7 mg