Describes the design and evaluation of a Spectronic 20-based detector as well as a simple system for postcolumn derivatization useful for metal-ion chromatographic detection. Both detection and derivatization can be performed in the ultra-violet (UV) mode using a low-cost UV-visible spectrophotometer and UV-region derivatization reagents. (JN)

Describes the equipment, procedures, and results for the determination of caffeine in beverages by high performance liquid chromatography. The method is simple, fast, accurate, and, because sample preparation is minimal, it is well suited for use in a teaching laboratory. (JN)

Describes an experiment that: (1) has a derivation step using readily available reagents; (2) requires limited manipulative skills, centering attention on methodology; (3) can be completed within the time constraints of a normal laboratory period; and (4) investigates materials that are easy to acquire and are of great technical/biological…

Voltammetry, the fundamental electrochemical experiment, is the measurement of the current which flows at an electrode as a function of the potential applied to the electrode. Such an experiment is discussed, focusing on factors which influence the shape of the current potential curve. (JN)

Procedures are provided for a flame emission experiment which covers five areas in a single laboratory exercise. These areas are: (1) the flame emission technique; (2) calibration plots; (3) interferences; (4) indirect flame emission analysis; and (5) techniques of removing interferences. Typical results obtained are discussed. (JN)

"Colloid titration" is a volumetric method for determining charged polyelectrolytes in aqueous solutions. The principle of colloid titration, reagents used in the procedure, methods of endpoint detection, preparation of reagent solutions, general procedure used, results obtained, and pH profile of colloid titration are considered. (JN)

Background information and experimental procedures are provided for an experiment in which three samples of saccharin (a nickel plating solution, a dilute cola drink, and a more concentrated cola drink) are analyzed and the data interpreted using five methods. Precision and accuracy are evaluated and the best method is selected. (JN)

Describes a colorimetric titration instrument usable in the undergraduate laboratory that fulfills the objectives of ruggedness, freedom from ambient light interference, and low cost. Although accessories can be added (raising the price), the basic instrument is low priced and can be used manually with a simple voltmeter. (JN)

Presents a series of experiments (involving immunological and serological techniques) in which a stained fabric is analyzed to determine if blood is present, and if so, whether it is of human origin. The experiments can be performed without expensive or sophisticated equipment and require only a minimal expenditure on consumable supplies. (JN)

Discusses the chemical nature of thermoplastic polymers and describes methods used to identify 29 of these substances. All methods selected are simple and rapid to use. (JN)

An experiment for determining polychlorinated biphenyl (PCB) isomers is described. The very low vapor pressures of PCB's allow them to be handled safely in the laboratory. In addition, this low volatility permits their analysis by thin-layer chromatography and recovery from the developed plate with effectively no evaporative losses. (JN)

Demonstrates construction of density constant and refractive index constant lines in triangular coordinate system on basis of systematic experimental determinations of density and refractive index for both homogeneous (single-phase) ternary liquid mixtures (of known composition) and the corresponding binary compositions. Background information,…

This experiment presents one direct titration for water soluble base and an indirect titration after dissolving a sample (oak ashes) in a known excess of acid. A titer method of calculation is given to allow use by students without knowledge of molarity-volume-mole calculations. (Author/JN)

A hydrodynamic modulation voltammetry (HMV) experiment involving use of simple hydrodynamic modulation procedures is described. Competing with time/equipment restrictions of most teaching laboratories (stopped-stirring and stopped-flow volumetry), students perform both batch and flow analyses and are introduced to analytical flow systems and the…

Presents an undergraduate experiment demonstrating sampling error. Selected as the sampling system is a mixture of potassium hydrogen phthalate and sucrose; using a self-zeroing, automatically refillable buret to minimize titration time of multiple samples and employing a dilute back-titrant to obtain high end-point precision. (CS)