Describes an open-ended chemistry laboratory project for organic chemistry laboratories. (SL)

Describes an experiment for an introductory chemistry laboratory for engineering students in the electroplating of dielectric substances. (SL)

Describes an undergraduate biochemical experiment involving the isolation and characterization of acid phosphatase from readily available materials. (Author/SL)

A list of demonstrations of discrepant events which have been found to stimulate the curiosity of students in science at the secondary school level are presented. A brief description of the materials and procedures for 15 of these demonstrations is outlined, with short explanations of concepts and principles involved. (MP)

Presents data on release of renin during direct and indirect stimulation of renal nerves. Conclusions show that renin release is influenced by change in activity of carotid and cardiopulmonary baroreceptor systems, and excitation of discrete areas of brain and hypothalamus by changes in renal sympathetic nerve. (Author/SA)

The increase in NMR relaxation rates as a result of dissolved paramagnetic species on the sample of superoxygenated drinking water is demonstrated. It is concluded that oxygen content in NMR samples is an important issue and can give rise to various problems in the interpretation of both spectroscopic and NMR imaging or relaxation experiments.

An experiment on kinetics of deactivation of carbonic anhydrase by removal of zinc is demonstrated. Carbonic anhydrase, the enzyme that catalyzes the interconversion of carbon dioxide and bicarbonate, requires on Zn(II) ion in its active site, and removal of the zinc cofactor by complexion to another ligand leaves the apoenzyme, which is totally…

A mixture of potassium hydroxide and alpha-naphthaldehyde (1) are heated under solvent-free conditions to produce 1-naphthoic acid (2) and 1-naphthalenemethanol (3). The experiment offers several advantages over many existing exercises including the ease of reaction workup, shorter reaction time, relative environmental friendliness of the…

A laboratory course called cytochrome c that focuses on the theme of biochemical research is presented. The students follow this course by incorporating team-investigation and self-directed experimentation that provides them an opportunity to experience the excitement of research.

The reduction of carbonyl groups by sodium borohydride though is a well-known reaction in most organic lab texts, a difficulty for an instructor adopting this reaction in a student lab is that it is too long. Using a microwave assisted organic synthesis solves this difficulty and one such reaction, which is the microwave-assisted reduction of…

Electrospray ionization (ESI) is a soft ionization technique that allows transfer of fragile biomolecules directly from solution into the gas phase. An instrumental analysis laboratory experiment is designed that would introduce the students to the ESI technique, major parameters of the ion trap mass spectrometers and some caveats in…

The addition of a dilute solution of bromine in carbon tetrachloride to a compound to test for carbon-carbon multiple bonds, which is one of the widely cited qualitative tests employed in organic chemistry is presented. Major advantages of this approach include the ease and rapidness of the procedure, the stability of the test solution over time,…

A thin-wall disposable Pasteur pipet is used as a vacuum-tight receptacle for air-sensitive compounds to ascertain their melting points. This technique is easy, economical, and successfully used for many years to develop air-sensitive samples for melting point determinations.

The preparation of libethenite, a double salt of copper(II) phosphate and copper(II) hydroxide presents the opportunity to discuss the prevalence of double salts in the environment, the relationship between solubility and stability in aqueous solution, the origin of the color of transition metal compounds and gravimetric analyses. Typical results…

A laboratory experiment designed to examine the entrance and exit effects in small electrochemical filter-press reactors used in the laboratory is presented. The single compartment of the filter-press reactor is filled with different turbulence promoters to study their influence as compared to the empty configuration.