Presents an improved technique for synthesizing acetanilide from nitrobenzene by reducing nitrobenzene with iron powder and hydrochloric acid. This experiment has been used successfully with 2,000 students during two semesters. (Author/SA)

Describes a convenient, inexpensive experiment in enzyme kinetics developed for the undergraduate biochemistry laboratory at the University of Virginia. Required are a single beam visible spectrophotometer with output to a recorder, a constant temperature, a commercially available enzyme, substrates, and buffers. (BT)

Describes a physical chemistry experiment that allows students to test the effect of ionic strength on the rates of a reaction between ions. The reduction of hexacyanoferrate III by ascorbic acid is detailed. Comparisons with the iodine clock reaction are made. (CS)

The synthesis of 1,4-diphenylbutadiene by means of the Wittig reaction is presented as suitable for organic chemistry students at the end of a basic laboratory program to apply laboratory skills and display understanding of the use of phase transfer catalysis and its application in syntheses. (CS)

An experiment is described in which undergraduate students can optimize the relative yield of sec-butylbenzene by varying molar ratio and temperature. (Author/SA)

Presents a classical demonstration of polarization for high school students. The initial state of this model, which demonstrates the important concepts of the optical and quantum problems, was developed during the 1973 summer program on lecture demonstration at the U.S. Naval Academy. (HM)

Describes briefly three experiments, which are presented by three physics teachers to share their ideas with other teachers and readers. These experiments are: (1) a simple hazemeter for window pollution assessment; (2) the speed of light; and (3) the ball-bearing electric motor. (HM)

Activities for exploring the school yard with children are suggested. Emphasis is on development of the senses, studying relationships, and conducting experiments. (SA)

This experiment is designed to acquaint the student with a macromolecular synthesis of a crown ether type compound. The starting materials are readily available and the product, a cyclic polyether, belongs to a class of compounds that has aroused the interest of chemist and biologist alike. (Author/BB)

This undergraduate experiment shows that the inclusion of an appropriate additive can have a very marked effect on the physical properties of a polymer. The polymer used is polypropylene and the additives are 2-hydroxy-4-octyloxy-benzophenone and benzophenone. (BB)

Presents nine selected physics notes which could be used in selected physics courses. Each includes the name of the author and a description of activities suggested. (HM)

Describes a short undergraduate experiment which helps in explaining the concept of entropy and in illustrating the second law of thermodynamics. (GA)

A modification of the Ames test for detecting carcinogens and mutagens using a strain of bacteria is described. A suggestion is given for checking the correctness of procedures by using particular hair dyes which have been shown to be mutogenic. (Author/SA)

Three derivations of the complete discharge time of a capacitor through a resistor are reviewed and examples of potential interest in the classroom are given. (Author/SA)

Presents two demonstrations which are intended for chemistry college students. These demonstrations are: (1) enhancement of concentration quenching by micelles; and (2) the thermite lecture demonstration. (HM)