1. Equilibrium
2. Analytical chemistry
3. Organic chemistry (especially organic solvents)
4. Chemical bonding
1. Environmental Sciences
Air pollution
Water pollution
Acid rain
Eutrophication in lakes and rivers (from dissolved nitrates and phosphates)
2. Geochemistry
Formation of sink holes by solution of underground limestone
Crystal formation\par
3. Biochemistry
Biochemical reactions
Fat-solubility of DDT, other pesticides\par
4. Medicine
Artificial kidneys for hemodialysis
Kidney and gallstone formation
Preparation of intravenous fluids
5. Meteorology
Rain, snow formation
1. The Process of Life Depends upon Solutions
Oxygen and carbon dioxide are carried in solution in blood.
Nutrients from foods we eat (simple sugars, amino acids, water soluble vitamins, etc.) are absorbed as particles dissolved in water.
Fat-soluble vitamins are ingested as part of fatty substances and are stored in fat in the body.
Urea and other excretory products are water soluble.
Bones and teeth are composed primarily of insoluble phosphates, which contribute to their strength and durability.
2. Altering Solubilities Often Results in Health Problems
Bacteria in the urinary tract can hydrolyze urea, producing ammoniaand changing urine’s pH. This lowers the solubility of magnesium ammonium phosphate (MgNH4PO4). This mineral (called struvite) precipitates as one type of kidney stone and must be removed surgically or broken up by ultrasound.}
High-protein intake increases the production of uric acid and urates. When their concentration exceeds their solubility, they often precipitate in various joints of the body. This condition is known as gout.
Water-soluble vitamins are excreted in urine and must be replenished daily, or deficiency symptoms may result. Fat-soluble vitamins (A, D, E) are stored in body fat. One generally has enough of these vitamins stored to last several years
3. Formation of Caves. Caves are formed because most rocks (especially limestone, gypsum, and dolomite) are soluble in water. Calcium carbonate, the primary component of limestone, dissolves in water rich in carbon dioxide to form calcium hydrogen carbonate. When the concentration of carbon dioxide decreases due to temperature change, pressure change, etc. as found in caves, solid calcium carbonate precipitates to form stalactites and stalagmites.
4. Boiler Scale. The same process described in (3) produces a deposit of calcium carbonate in water pipes and in boilers. When water saturated with carbon dioxide seeps through the ground it reacts with limestone to form soluble calcium hydrogen carbonate. When it is heated, carbon dioxide is driven off and insoluble calcium carbonate forms.
5. Acid Rain. Acid rain reacts with monuments, statues, buildings, etc. composed primarily of calcium carbonate to form the more soluble calcium sulfate.
6. Photography. Insoluble silver halides (AgI, AgBr, AgCl) are used to manufacture photographic film and paper.
7. Extraction of Magnesium from Sea Water. Hydroxide ion is added to sea-water to precipitate magnesium hydroxide, thus separating it from the more abundant sodium ions. The magnesium hydroxide is neutralized with hydrochloric acid. The resulting solid magnesium chloride is melted; electrolysis of the molten salt gives magnesium metal.
1. “Solutions: Ionic and Molecular,” Coronet laser videodisc (also on videocassette). Includes discussion questions.
2. “Doing Chemistry,” laser videodisc set.
Side C. DMEX C21 “Equilibrium Crystallization”
DMEX C22 “Supersaturation”
DEMO C25 “Aqueous and Nonaqueous Solvents
EXPT C28 “Solution Formation”
EXPT C20 “Effect of Temperature on Solubility”
Extensive hard copy descriptions and worked out experiments are provided with the\par disk. From American Chemical Society, 1155-16th St., N.W., Washington, D.C. 20036.
3. Software published by Project SERAPHIM, Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue. Madison, Wl 53706-1396: (608) 263- 2837 (voice) or (608) 262-0381 (FAX).
a. For the Apple II computer running on ProDOS: AR 303
b. For the Apple II computer: AP 310, AP 502
c. For IBM PCs and PC-compatibles: PC 2501}
(page 19 & 20)
