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- Arrange the following compounds in order of their expected increasing solubility in water: Br2, KBr, toluene (C7H8, a constituent of gasoline).
Problem 48
- Ethyl alcohol, CH3CH2OH, is miscible with water at 20 °C, but pentyl alcohol, CH3CH2CH2CH2CH2OH, is soluble in water only to the extent of 2.7 g/100 mL. Explain.
Problem 52
- Pentyl alcohol, CH3CH2CH2CH2CH2OH, is miscible with octane, C8H18, but methyl alcohol, CH3OH, is insoluble in octane. Explain.
Problem 53
Problem 54
The dissolution of CaCl2(s) in water is exothermic, with ΔHsoln= - 81.3 kJ>mol. If you were to prepare a 1.00 m solution of CaCl2 beginning with water at 25.0 °C, what would the final temperature of the solution be in °C? Assume that the specific heats of both pure H2O and the solution are the same, 4.18 J>1K g2.
Problem 56
Assuming that seawater is an aqueous solution of NaCl, what is its molarity? The density of seawater is 1.025 g/mL at 20 °C, and the NaCl concentration is 3.50 mass %.
Problem 58b
Propranolol 1C16H21NO22, a so-called beta-blocker that is used for treatment of high blood pressure, is effective at a blood plasma concentration of 50 ng/L. Express this concen- tration of propranolol in the following units: (b) Molarity
- Residues of the herbicide atrazine C8H14ClN5 in water can be detected at concentrations as low as 0.050 mg/L. Express this concentration of atrazine in the following units: (a) Parts per billion (assume a solution density of 1.00 g/mL)
Problem 59
Problem 59a
Residues of the herbicide atrazine (C8H14ClN5) in water can be detected at concentrations as low as 0.050 µg/L. Express this concentration of atrazine in the following units: (a) Parts per billion (assume a solution density of 1.00 g/mL)
Problem 59b
Residues of the herbicide atrazine (C8H14ClN5) in water can be detected at concentrations as low as 0.050 µg/L. Express this concentration of atrazine in the following units: (b) Molarity
- How would you prepare each of the following solutions? (c) A solution of methyl alcohol (methanol) and water in which Xmethanol = 0.15 and Xwater = 0.85
Problem 60
- How would you prepare each of the following solutions? (a) 100 mL of a 155 ppm solution of urea, CH4N2O, in water
Problem 61
Problem 61b
How would you prepare each of the following solutions? (b) 100 mL of an aqueous solution whose K+ concentration is 0.075 M
Problem 62
How would you prepare 165 mL of a 0.0268 M solution of benzoic acid 1C7H6O22 in chloroform 1CHCl32?
- Which of the following solutions is more concentrated? 1.75 M glucose or 1.75 m glucose in water?
Problem 64
Problem 64a
Which of the following solutions is more concentrated? (a) 0.500 M KCl or 0.500 mass % KCl in water
- Which of the following solutions has the higher molarity? (a) 10 ppm KI in water or 10,000 ppb KBr in water
Problem 65
- What is the mass percent concentration of the following solutions? (a) Dissolve 0.655 mol of citric acid, C6H8O7, in 1.00 kg of water. (b) Dissolve 0.135 mg of KBr in 5.00 mL of water. (c) Dissolve 5.50 g of aspirin, C9H8O4, in 145 g of dichloromethane, CH2Cl2.
Problem 66
- What is the molality of each solution prepared in Problem 13.66?
Problem 67
- The ozone layer in the Earth's stratosphere has an average total pressure of 10 mm Hg 11.3 * 10-2 atm2. The partial pressure of ozone in the layer is about 1.2 * 10-6 mm Hg 11.6 * 10-9 atm2. What is the concentration of ozone in parts per million, assuming that the average molar mass of air is 29 g/mol?
Problem 68
- A person is medically considered to have lead poisoning if he or she has a concentration of greater than 10 mg of lead per deciliter of blood. What is this concentration in parts per billion? Assume that the density of blood is the same as that of water.
Problem 69
- What is the concentration of each of the following solutions? (b) The mole fraction of each component of a solution pre- pared by dissolving 2.25 g of nicotine, C10H14N2, in 80.0 g of CH2Cl2
Problem 70
- Household bleach is a 5.0 mass % aqueous solution of sodium hypochlorite, NaOCl. What is the molality of the bleach? What is the mole fraction of NaOCl in the bleach?
Problem 71
Problem 72
The density of a 16.0 mass % solution of sulfuric acid in water is 1.1094 g/mL at 25.0 °C. What is the molarity of the solution?
- What is the molality of the 40.0 mass % ethylene glycol 1C2H6O22 solution used for automobile antifreeze?
Problem 74
- Ethylene glycol, C2H6O2, is a colorless liquid used as auto-mobile antifreeze. If the density at 20 °C of a 4.028 m solu- tion of ethylene glycol in water is 1.0241 g/mL, what is the molarity of the solution? The molar mass of ethylene glycol is 62.07 g/mol
Problem 75
- Nalorphine 1C19H21NO3 2, a relative of morphine, is used to combat withdrawal symptoms in narcotics users. How many grams of a 1.3 * 10-3 m aqueous solution of nalor-phine are needed to obtain a dose of 1.5 mg?
Problem 76
- How many grams of water should you add to 32.5 g of sucrose, C12H22O11, to get a 0.850 m solution?
Problem 77
Problem 78a
A 0.944 M solution of glucose, C6H12O6, in water has a density of 1.0624 g/mL at 20 °C. What is the concentration of this solution in the following units? (a) Mole fraction
Problem 78b
A 0.944 M solution of glucose, C6H12O6, in water has a density of 1.0624 g/mL at 20 °C. What is the concentration of this solution in the following units? (b) Mass percent
Problem 78c
A 0.944 M solution of glucose, C6H12O6, in water has a density of 1.0624 g/mL at 20 °C. What is the concentration of this solution in the following units? (c) Molality