Using a joystick module, we followed the movement of a chaotic magnetic pendulum. The pendulum bar was attached to a joystick that served as a pivot point and biaxial angular motion sensor. Using an Arduino board, we could follow the position as a function of time along both the "x" and "y"-axis and draw a graph showing the…

A virtual reality (VR) session was introduced to an advanced inorganic chemistry class, a class available to junior and senior undergraduate students at the University of California, Los Angeles. The VR session helped the students to learn complicated aspects of metal coordination chemistry and molecular orbitals via an immersive three-dimensional…

Understanding the concepts of quantum mechanics has always been a challenge for undergraduate students. This is especially so because many of the introductory (analytically solvable) systems and problems discussed in textbooks are seemingly abstract. Using approximate experimental demonstrations of such systems and problems have been shown to be…

Understanding reflection and refraction are an integral part of school and college learning. In nature even birds and fish (Archer fish) very skillfully use refraction to strike down prey present above or below the water surface. Fermat's principle allows one to look beyond the reasons behind the laws governing the reflection and refraction. A…

A bioinformatics laboratory experiment was designed to help undergraduate students learn RNA structure and function in biochemistry courses. In this laboratory experiment, students used 5S rRNAs as material to predict secondary structure and visualize three-dimensional (3D) structure. Students first downloaded molecular information from the 5S…

The application of the Reaction Monte Carlo (RxMC) algorithm to standard textbook problems in chemical reaction equilibria is discussed. The RxMC method is a molecular simulation algorithm for studying the equilibrium properties of reactive systems, and therefore provides the opportunity to develop computer-based "experiments" for the…

A series of computer-based laboratory experiments have been developed to aid undergraduate students in appreciating the three-dimensional nature of chemistry and biochemistry. Both lower- and upper-division experiments have been developed. Students are introduced to the use of ChemDraw for the production of professional-quality molecular…

The electrophilic addition of a hydrohalic acid (HX) to an alkene is often one of the first reactions learned in second-year undergraduate organic chemistry classes. During the ensuing discussion of the mechanism, it is shown that this reaction follows Markovnikov's rule, which states that the hydrogen atom will attach to the carbon with fewer…

The concept of wave-particle duality in quantum theory is difficult to grasp because it attributes particle-like properties to classical waves and wave-like properties to classical particles. There seems to be an inconsistency involved with the notion that particle-like or wave-like attributes depend on how you look at an entity. The concept comes…

An exercise in molecular modeling that demonstrates the distinctive features of Fischer and Schrock carbene complexes is presented. Semi-empirical calculations (PM3) demonstrate the singlet ground electronic state, restricted rotation about the C-Y bond, the positive charge on the carbon atom, and hence, the electrophilic nature of the Fischer…

In this experiment, students carry out a modern organocatalytic reaction using IMes·HCl and NaOH to catalyze the formation of 1,3,4-triphenylcyclopentene from cinnamaldehyde and chalcone in water. Deprotonation of IMes·HCl with NaOH forms the "N"-heterocyclic carbene IMes that reacts with cinnamaldehyde to form a homoenolate equivalent…

A homology modeling laboratory experiment has been developed for an introductory molecular modeling course for upper-division undergraduate chemistry students. With this experiment, students gain practical experience in homology model preparation and assessment as well as in protein visualization using the educational version of PyMOL…

Electron-atom collisions in gases are an aspect of atomic physics. Three experiments in this field employing a thyratron are described: (i) the Ramsauer-Townsend effect, (ii) the excitation and ionization potentials of xenon and (iii) the ion-electron recombination after interrupting the electric discharge.

Unlike most spectroscopic calibrations that are based on the study of well-separated features ascribable to the different components, this laboratory experience is especially designed to exploit spectral features that are nearly overlapping. The investigated system consists of a binary mixture of two commonly occurring minerals, calcite and…

The heterogeneous equilibrium of the solubility of calcium hydroxide in water is used to predict both its solubility product from solubility and solubility values from solubility product when inert salts, in any concentration, are present. Accepting the necessity of including activity coefficients to treat the saturated solution of calcium…