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.

The S[subscript N]2 reaction of 1-bromohexane and 1-bromobutane with potassium acetate is introduced to address the shortage of suitable laboratory experiments in organic laboratory. The experiment offers a review of some common laboratory techniques including the use of infrared spectroscopy to identify functional groups, the use of GC-MS…

In this article, the authors discuss a unique and challenging laboratory exercise called, the paint-stir-stick submarine, that keeps the students enthralled. The paint-stir-stick submarine fits beautifully with the National Science Education Standards Physical Science Content Standard B, and with the California state science standards for physical…

An experiment is suitable for fourth-year undergraduate and graduate students in which the nature of the semiconductor materials through determination of flat-band potential using the Mott-Schottky equation is explored. The experiment confirms the soundness of the technique.

A simple and cost-effective experiment for the development and characterization of semiconductors using Uv-vis spectroscopy is described. The study shows that the optical properties of ZnO films can be easily modified by forming Zn[subscript 1-x] Co[subscript x]O solid solutions via spray pyrolysis.

Students developing their labs lead them to enhance the laboratory experience. This benefits the students as they learn more about the experiments and they get benefit by peers led labs through a more fluid discussion.