Describes a semester-long study of microorganisms in an aquarium as performed by a beginning microbiology class. Gives results and conclusions drawn by students utilizing many ecological principles to interpret the results. Similar projects could be used from beginning high school through advanced college biology. (EB)

Discusses the chemical nature of gallstones and theories related to their formation. Also discusses experimental procedures used to identify chemical constituents of gallstones, indicating that cholesterol is found in almost 75 percent of stones examined. (JN)

Describes an experiment in which students: (1) synthesize tris(acetylacetonato)iron(III), tris(diethyldithiocarbamato)iron(III), and chlorobis(diethyldithiocarbmamato)iron(III); (2) are given a sample of potassium hexocyanoferrate(III); and (3) are then asked to measure the room temperature of these samples using the Guoy technique. Background…

Using different supporting electrolytes, the influence of complex-forming equilibria on migration velocities of strontium-90 and yttrium-90 can be demonstrated in this experiment. Includes procedures and materials needed. (SK)