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We describe a laboratory experiment that serves as an introduction to solid-state and materials science, a topic that requires additional attention in the undergraduate chemistry laboratory curriculum. The experiment illustrates the long-range translational order, crystal growth, and the macroscopic manifestations of that order. This is demonstrated through the preparation and characterization of large, well-formed bismuth crystals, an aesthetically pleasing product. The characterization of the grown bismuth crystals involves determination of melting point and enthalpy of fusion via differential scanning calorimetry. The temperature dependence of the electrical resistance of grown bismuth crystals is also measured. Students are encouraged to consider the effect of metallic bonding interactions on the melting of the crystal samples and on their ability to conduct electricity. Students also analyze how the impurities influence the melting point and the electrical properties. The experiment is suitable for u...

Cement is a paste of calcium silicate hydrates, polymerized into a densely cross-linked matrix. Although cement has been known and used for two thousand years, even today its chemistry is not fully...

Heat capacity is one of the most fundamental of all physical properties, yet it is exceedingly unlikely that it will be determined experimentally for all materials. Heat capacity plays an important role in understanding thermodynamic stability, from the perspective of relative enthalpies, entropies, and Gibbs energies of comparative compounds. Therefore, methods to estimate a material's heat capacity could be very useful. We outline such a method for complex inorganic solids, based on additivity of constituent species. This method is especially useful at and above about 150 K, often giving results within a few percent of experimental determinations. Several examples are presented, and the utility and limitations of this method of heat capacity estimation and its uses in teaching are discussed.

Students have been asked to summarize their "Learning Philosophy" in a short, written, individual assignment, somewhat similar to professors' "Teaching Philosophy" statements. In part, the "Learning Philosophy" statements were based on a survey designed to assess the learning styles of individual students. This simple activity has helped the students focus on their learning goals and efficiently provided their professor with knowledge of the learning objectives of the students, both individually and collectively.

Many commercial products change color with a change of temperature. How do they do it? The processes responsible for the two major categories of commercial thermochromic coloring agents are presented, along with a description of applications of thermochromic materials.

Despite the number and variety of phase transitions that are observed, they are all thermodynamically bound by the common feature that the Gibbs energy function (G ) must be continuous upon passing...

Carbonless copy paper, used to make countless copies of forms, is a 109 kg business annually. Copies are made when the pressure of a pen ruptures microcapsules that contain a dye precursor, initiat...

The method of quantity calculus treats physical quantities as the product of a numerical value and a unit. This method, known for more than a century and internationally recommended for handling of physical quantities, is not used as extensively in textbooks and teaching as it could be. This paper gives some background to the methodology, and shows examples, suitable for teaching to undergraduate students, of the use of quantity calculus to provide unambiguous representations of physical quantities in tables and graphs.

In order to energize my first-year students, I held a class to which the students brought chemistry-related questions, to be answered by a team of chemists. The session proved to be very interesting, rejuvenating the students' enthusiasm for the class and providing me with useful insight into their interests.

57. Bits and pieces, 22. Output from the DSC is digitized by an interface circuit board that is inserted in the computer system board.