Provides answers to these two questions: (1) What can be said about molecular structure? and (2) What are the foundations of theoretical chemistry? Indicates that students can be encouraged to think critically about primitive concepts of their subject (such as bonds and molecules) rather than passively accept them as truth. (JN)

Shows how physics, arguably the most confusing of the sciences, can be told as an interesting and informative tale of determination and discovery that even middle school students can grasp, presenting the story of the scientific detective work that eventually convinced the world that the atom existed. (SM)

A clarification of concepts and a comparative analysis of chirality as a consequence of stereogenic center and axes are provided by considering the different possibilities for the archetypical molecule Cabcd. The key difference between Cabcd and abC=C=Ccd and, by extension, between molecules incorporating a stereogenic axis, is in the number of…

Sharpless asymmetric dihydroxylation is developed that focuses on the varying enantiomeric excess of the product diols based on the structures of the alkenes being oxidized. The experimental sequence enables investigation of this reaction in terms of the different chiral ligands being used.

The interplay between a nucleus and an electron pair is explained through a basic application of an electrostatic and balanced model to determine the correlated and repulsive movements of the electron pair. The stable correlation depends on the positive charge produced by the combined force, which in turn establishes a negative potential energy.

Complexes of pyrazole-derived ligands are very popular due to the ability of the pyrazolato anion to form bridged polymetallic compounds in which the metals are held close enough to react with small molecules or facilitate magnetic exchange. The preparation of monodentate pyrazole and 3,5-dimethylpyrazole (DMHpz) nickel species and the…

Bond stereochemistry in polyatomic hydrides is explained in terms of the principle of bond energies maximization, which yields X-H straight bonds and suggests the formation of appropriate sp hybrids on the central atom. An introduction to the electron charge distribution in molecules is given, and atomic, overlap, gross and formal charges are…

A study identifies a compound from a set of monoterpenes using infrared (IR) and one-dimensional (1D) nuclear magnetic resonance (NMR) techniques. After identifying the unknown, each carbon and proton signal can be interpreted and assigned to the structure using the information in the two-dimensional (2D) NMR spectra, correlation spectroscopy…

A Lattice Energy Spreadsheet by Christopher King, which can help instructors and students to easily calculate crystal lattice energies in many binary compounds, is introduced.

A practical laboratory experiment is described that illustrates the application of fluorescence resonance energy transfer to the study of protein-ligand binding. The affinities of wild-type and mutant human carbonic anhydrase II for dansylamide were determined by monitoring the increase in ligand fluorescence that occurs due to energy transfer…

What, if anything, do teachers need to know about how the brain works to improve teaching and learning? After all, a plumber needs to know how to stop leaks--not the molecular structure of water. And one can learn how to use a computer without knowing how a computer chip works. Likewise, teachers need to know how to help students develop…

Presents various ideas on the origin of life including very early ideas, Oparin's view, and an alternative view related to carbonaceous chondrites. Outlines one currently tenable hypothesis in the formation of the solar system and explains the method involved in detecting polyatomic molecules in dark nebulae. (GS)

Explores the extent to which, in polycyclic hydrocarbons, the total pi electron population tends to form small (4n plus 2) groups and avoid the formation of 4n groups. Also discusses the relation of this trend to resonance energy stabilizations. (JN)

Describes steps (using monochiral and multichiral molecules) to enable students to arrive with relative ease at correct stereochemical relationships. The approach assumes familiarity with Fischer projection formulas and assignment of R and S absolute configurations. (JN)