A short course covering problems of increasing difficulty in chemical kinetics explored via Excel spreadsheet exercises is summarized. It is offered as part of a physical chemistry course. This 10-h computer course is offered parallel to the theory covered in the class and allows kinetics to be explored by handson computer work. Students progress at their own rate. At the end of the course, students are examined individually in a 2-h practical examination.The course is ideally suited to small classes, although with good organization and access to large computer laboratories, large classes can be handled. Students generally enjoy the course because it gives them a visual representation of kinetics and at the same time improves their computer skills. Students should have an introductory knowledge of kinetics and Excel spreadsheets and be able to plot straight lines and enter formulas.The course begins with simple straight-line work to confirm the order of a suitable reaction, using data acquired in the laboratory. The oxidation of ethanol by dichromate is studied. Plotting the required graphs for zero, first, and second order allows the students to establish the order of the reaction with respect to the HCrO 4 -concentration. Next, students determine a missing infinity reading from a series of data using the principle of the sum of the squares of the deviations being a minimum for the correct value. The reaction studied here is the hydrolysis of methyl acetate. This is followed by a study of the simultaneous decay of two radioisotopes to determine the individual rate constants. Students then explore several aspects of consecutive first-order reactions: concentration profiles of reactant A, and products B and C versus time for different values of the rate constants k 1 and k 2 and the time at which B reaches its maximum concentration for a certain k 1 and k 2 value. Finally, an in-depth study is made of a multistep reaction process exemplified by the successive chlorination of benzene: students use the necessary equations, which can be complex, to calculate concentrations of benzene and the mono-, di-, and trisubstituted chlorobenzenes expressed as ratios with respect to the initial concentration of the benzene. They then plot this fractional concentration versus moles of chlorine consumed per mole of benzene initially present to see the formation of the different species. Supporting Information AvailableA detailed description of the course and Excel spreadsheets. This material is available via the Internet at

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The Egyptians were known in the ancient world as experts in many applied chemistry fields such as metallurgy, wine and beer making, glass making, paper manufacture, paint pigments, dyes, cosmetics, perfumes, and pharmaceuticals. They made significant developments in the extraction of metals from their ores, especially copper and gold. The Egyptians developed a writing surface from the papyrus plant and used naturally occurring inorganic salts as paint pigments; they also made the first synthetic pigment, Egyptian blue, developed as early as 3000 B.C.E. The Leyden and Stockholm papyri give information on numerous chemical processes, dating to about 300 C.E., but copied from earlier sources. This article describes an overview of the various chemical activities that took place in ancient Egypt from which it can be deduced that the ancient Egyptians were among the first practicing chemists. In fact the word “chemistry” can be traced to the name the ancients used when referring to ancient Egypt.

The electrochemical oxidation of the substituted phenol 2,6-di-t-butylphenol is studied at platinum electrodes using a number of 1-butyl-3-methylimidazolium (bmim) ionic liquids (BF 4 , PF 6 and N(CF 3 SO 2 ) 2 ), and compared with the oxidation obtained using a traditional solvent/electrolyte system (CH 3 OH/CH 2 Cl 2 and LiClO 4 ). The electrolysis leads to anodic coupling, resulting in the corresponding diphenoquinone, which upon reduction produces the biphenol. Best results were obtained for the conventional solvent and electrolyte, where the oxidation was found to take place via an indirect method. It was found that the ionic liquids performed better upon dilution with a suitable solvent such as acetonitrile, yielding higher conductivities due to ion separation. Dilution studies were performed with acetonitrile, methanol, dichloromethane and acetone and the resulting increase in conductivity of the ionic liquid was in the order: acetonitrile [ methanol [ acetone [ dichloromethane. This trend is in line with the dielectric constant and the dipole moment of the solvent used. It was found that the electrolysis proceeded best in the following order: conventional solvent/electrolyte [ ionic liquid suitably diluted [ ionic liquid. Among the ionic liquids, best results were obtained for [bmim] [BF 4 ]. Cyclic voltammetry data was used to further explain the electrolysis as a function of dilution.

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