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- Examine the structures of phenol and naphthol shown here and explain why phenol is so much more soluble in water at 25 °C (87 g/L) compared to naphthol (0.74 g/L).
Problem 1
- Use Henry’s Law to determine the molar solubility of helium at a pressure of 1.0 atm and 25 °C.
Problem 5
- You can purchase hydrochloric acid in a concentrated form that is 37.0% HCl by mass and that has a density of 1.20 g>mL. Describe exactly how to prepare 2.85 L of 0.500 M HCl from the concentrated solution.
Problem 6
- Calculate the freezing point and boiling point of a solution containing 7.55 g of ethylene glycol (C2H6O2) in 85.7 mL of ethanol. Ethanol has a density of 0.789 g/cm³.
Problem 8
- What is the required concentration (in percent by mass) for an aqueous ethylene glycol (C2H6O2) solution to have a boiling point of 104.0 °C?
Problem 9
- What is the boiling point of an aqueous solution with a vapor pressure of 20.5 torr at 25 °C? (Assume a nonvolatile solute.)
Problem 11
Problem 29
Pick an appropriate solvent from Table 13.3 to dissolve each substance. State the kind of intermolecular forces that would occur between the solute and solvent in each case. a. motor oil (nonpolar) b. ethanol (polar, contains an OH group) c. lard (nonpolar) d. potassium chloride (ionic)
Problem 30a,c,d
Pick an appropriate solvent from Table 13.3 to dissolve each substance. State the kind of intermolecular forces that would occur between the solute and solvent in each case. a. isopropyl alcohol (polar, contains an OH group) c. vegetable oil (nonpolar) d. sodium nitrate (ionic)
Problem 30b
Pick an appropriate solvent from Table 13.3 to dissolve each substance. State the kind of intermolecular forces that would occur between the solute and solvent in each case. b. sodium chloride (ionic)
Problem 31
Which molecule would you expect to be more soluble in water: CH3CH2CH2OH or HOCH2CH2CH2OH?
- Which molecule would you expect to be more soluble in water: CCl4 or CH2Cl2?
Problem 32
Problem 33
For each compound, would you expect greater solubility in water or in hexane? Indicate the kinds of intermolecular forces that occur between the solute and the solvent in which the molecule is most soluble. a. glucose
Problem 34
For each compound, would you expect greater solubility in water or in hexane? Indicate the kinds of intermolecular forces that would occur between the solute and the solvent in which the molecule is most soluble. d. ethylene glycol
- When ammonium chloride (NH4Cl) is dissolved in water, the solution becomes colder: a. Is the dissolution of ammonium chloride endothermic or exothermic? b. What can you conclude about the relative magnitudes of the lattice energy of ammonium chloride and its heat of hydration? c. Sketch a qualitative energy diagram similar to Figure 13.7 for the dissolution of NH4Cl. d. Why does the solution form? What drives the process?
Problem 35
Problem 36a
When lithium iodide (LiI) is dissolved in water, the solution becomes hotter. a. Is the dissolution of lithium iodide endothermic or exothermic?
Problem 36b
When lithium iodide (LiI) is dissolved in water, the solution becomes hotter. b. What can you conclude about the relative magnitudes of the lattice energy of lithium iodide and its heat of hydration?
Problem 36c
When lithium iodide (LiI) is dissolved in water, the solution becomes hotter. c. Sketch a qualitative energy diagram similar to Figure 13.7 for the dissolution of LiI.
Problem 36d
When lithium iodide (LiI) is dissolved in water, the solution becomes hotter. d. Why does the solution form? What drives the process?
Problem 37
Silver nitrate has a lattice energy of -820 kJ/mol and a heat of solution of 22.6 kJ/mol. Calculate the heat of hydration for silver nitrate.
Problem 38
Use the data to calculate the heats of hydration of lithium chloride and sodium chloride. Which of the two cations, lithium or sodium, has stronger ion–dipole interactions with water? Why?