A spectroscopic experiment is presented that reveals that the hydrophobically end-modified water-soluble polymeric fluorophore, pyrene end-capped poly(ethylene oxide) (PYPY), interacts differently with [alpha], [beta], and [gamma]-cyclodextrins (CD) to form supramolecular inclusion complexes. The emission spectrum of PYPY in aqueous solution shows…

Orbital exponent optimization in the elementary ab-initio VB calculation of the ground states of H[subscript 2][superscript +], H[subscript 2], He[subscript 2][superscript +], He[subscript 2] gives a fair description of the exchange-overlap component of the interatomic interaction that is important in the bond region. Correct bond lengths and…

To visualize what takes place in a chromatography column, enlarge the molecules to human size and expand the columns to keep the ratio of size of molecule to size of column the same. If we were molecules, what would the columns be like? A typical gas chromatography (GC) capillary column would be 50 x 10 [superscript 6] 6 km (31 million mi) long,…

We have used the recently developed method for rapid measurement of maximum density temperature to determine the rate at which hydrogen and deuterium isotope exchange takes place when a sample of heavy water is exposed to the atmosphere. We also provide a simple explanation for the observed linear rate of transition. (Contains 2 figures.)

In this article, the authors provide a brief overview of the emerging field of nanoscience and why it is an important area of education. They next explain the science behind the new nanoparticulate sunscreens, describe the different elements of the unit, and reflect on some of the opportunities and challenges of teaching nanoscience at the high…

Fruit batteries and saltwater batteries are excellent ways to explore simple circuits in the classroom. These are examples of air batteries in which metal reacts with oxygen in the air in order to generate free electrons, which flow through an external circuit and do work. Students are typically told that the salt or fruit water acts as an…

A new set of d orbitals, constructed as a linear combination of the omnipresent set of d[subscript xy], d[subscript yz], d[subscript xz], d[subscript x[superscript 2]-y[superscript 2]], and d[subscript z[superscript 2]] orbitals, is suitable for the discussion of octahedral transition-metal complexes. The main feature of the newly derived set…

A simplified treatment of the traditional theory of solvatochromism, attributed to Bayliss and McRae, is presented and used to describe the four main types of dipolar and dispersive physical interactions between solute and solvent. The theory is extended so that it may also be used to describe barochromism (pressure-induced spectroscopic shifts).…

A demonstration of the damping effect of an oil monolayer on water waves is described. The history of this remarkable demonstration--with a 2000 (or more) year span--and a brief explanation in terms of the properties of water and the monolayer are presented. If a layer of olive oil, one molecule thick (about one-ten millionth of a centimeter), is…

The 1935 debate opposing Einstein, Podolsky and Rosen to Bohr elicited so many comments and developments, both theoretical and experimental, until this day, that the main point at stake at that time can be overlooked by modern readers, especially students. This paper draws the reader's attention to the historical background of Einstein's paper and…

An undergraduate organic chemistry experiment demonstrating real-life application of GC-MS to arson accelerant identification is described. Students are given the task of comparing a sample recovered from a "crime scene" to that from a "suspect's clothing". Accelerants subjected to different conditions are recovered using a quick and simple…

Development of learning progressions has been at the forefront of science education for several years. While understanding students' conceptual development toward "big ideas" in science is extremely valuable for researchers, science teachers can also benefit from assessment tools that diagnose their students' trajectories along the learning…

A computational experiment aimed to create and systematically analyze models of simple cation hydrates is presented. The changes in the structure (bond distances and angles) and the electronic density distribution of the solvent and the thermodynamic parameters of the hydration process are calculated and compared with the experimental data. The…

Heterogeneous, gas-solid processes constitute an important class of catalytic reactions that play a key role in a variety of applications, such as industrial processing and environmental controls. Heterogeneous catalytic chemistry can be demonstrated in a simple heated flow reactor containing a fragment of the catalytic converter from a vehicular…

The knowledge of historical facts can help teachers and students to correctly appreciate a variety of scientific theories. It is important to be aware of the evolution of the basic concepts, particularly the ones our students find very abstract and therefore difficult to understand. Historical knowledge of chemical concepts will allow us to…