Problem 64
What is the concentration of a NaCl solution, in (m/v)%, prepared by diluting 65 mL of a saturated solution, which has a concentration of 37 (m/v)%, to 480 mL?
- What is an electrolyte?
Problem 67
Problem 69
What does it mean when we say that the concentration of Ca2+ in blood is 3.0 mEq/L?
Problem 72a
Calculate the mass needed for each of the following ion equivalents:
a. 0.25 Eq Ca2+
Problem 73
The concentration of Cl- ion in blood is approximately 100 mEq/L. How many milliliters of blood would be needed to obtain 1.0 g of Cl- ions?
Problem 80
What does it mean when we say that a 0.15 M NaCl solution is isotonic with blood, whereas distilled water is hypotonic?
Problem 81b
Which of the following solutions has the higher osmolarity?
b. 0.30 M NaOH or 3.0% (m/v) NaOH
Problem 82
Which of the following solutions will give rise to a greater osmotic pressure at equilibrium: 5.00 g of NaCl in 350.0 mL water or 35.0 g of glucose in 400.0 mL water? For NaCl, MW = 58.5 amu; for glucose, MW = 180 amu.
Problem 84
An isotonic solution must be approximately 0.30 osmol/L. How much KCl is needed to prepare 175 mL of an isotonic solution?
Problem 85
Uric acid, the principal constituent of some kidney stones, has the formula C5H4N4O3. In aqueous solution, the solubility of uric acid is only 0.067 g/L. Express this concentration in (m/v)%, in parts per million, and in molarity.
Problem 86
Emergency treatment of cardiac arrest victims sometimes involves injection of a calcium chloride solution directly into the heart muscle. How many grams of CaCl2 are administered in an injection of 5.0 mL of a 5.0% (m/v) solution? How many milliequivalents of Ca2+?
Problem 92a
Ammonia, NH3, is very soluble in water (51.8 g/L at 20 °C and 760 mmHg).
a. Show how NH3 can hydrogen bond to water.
Problem 93a
Cobalt(II) chloride, a blue solid, can absorb water from the air to form cobalt(II) chloride hexahydrate, a pink solid. The equilibrium is so sensitive to moisture in the air that CoCl2 is used as a humidity indicator.
a. Write a balanced equation for the equilibrium. Be sure to include water as a reactant to produce the hexahydrate.
Problem 94
How many milliliters of 0.150 M BaCl2 are needed to react completely with 35.0 mL of 0.200 M Na2SO4? How many grams of BaSO4 will be formed?
Problem 95a
Many compounds are only partially dissociated into ions in aqueous solution. Trichloroacetic acid (CCl3CO2H), for instance, is partially dissociated in water according to the equation
CCl3CO2H(aq) → H+(aq) + CCl3CO2⁻ aq)
For a solution prepared by dissolving 1.00 mol of trichloroacetic acid in 1.00 kg of water, 36.0% of the trichloroacetic acid dissociates to form H+ and CCl3CO2⁻ ions.
a. What is the total concentration of dissolved ions and molecules in 1 kg of water?
Problem 95b
Many compounds are only partially dissociated into ions in aqueous solution. Trichloroacetic acid (CCl3CO2H), for instance, is partially dissociated in water according to the equation
CCl3CO2H(aq) → H+(aq) + CCl3CO2⁻ aq)
For a solution prepared by dissolving 1.00 mol of trichloroacetic acid in 1.00 kg of water, 36.0% of the trichloroacetic acid dissociates to form H+ and CCl3CO2⁻ ions.
b. What is the freezing point of this solution? (The freezing point of 1 kg of water is lowered 1.86 °C for each mole of solute particles.)
Problem 96a
Hyperbaric chambers, which provide high pressures (up to 6 atm) of either air or pure oxygen, are used to treat a variety of conditions, ranging from decompression sickness in deep-sea divers to carbon monoxide poisoning. Look up the solubility of O2, N2, CO, and CO2 in water at standard temperature and pressure (1 atm, 25 °C).
a. Explain the trends in relative solubility for these gases.
Problem 96b
Hyperbaric chambers, which provide high pressures (up to 6 atm) of either air or pure oxygen, are used to treat a variety of conditions, ranging from decompression sickness in deep-sea divers to carbon monoxide poisoning. Look up the solubility of O2, N2, CO, and CO2 in water at standard temperature and pressure (1 atm, 25 °C).
b. Explain how elevated pressures in a hyperbaric chamber be used to treat decompression sickness (excess N2 in blood) and carbon monoxide poisoning.
Problem 98b
Look up the composition of Ringer's solution used in the treatment of burns and wounds.
b. What is the osmolarity of the solution? Is it hypertonic, isotonic, or hypotonic with blood plasma (0.30 osmol)? Discuss possible medicinal reasons for the osmolarity of the solution.
Problem 99b
To prevent accumulation of ice on roads and sidewalks, many municipalities (and home-owners) will apply de-icing compounds to 'melt' the ice by lowering the freezing point.
b. Some de-icing compositions include dyes or colored compounds called indicators. Why?
Problem 100b
Many carbonate minerals are insoluble in water and appear in water pipes as 'scale.'
b. Why is scale formation typically only a problem in hot water pipes?
Problem 101a
Research information related to dialysis and answer the following questions:
a. What is the difference between hemodialysis and peritoneal dialysis?
Ch.9 Solutions