In a chemistry course for students not majoring in science, there is more to learn than some memorized facts: the student can find, in most non-major chemistry texts, the definition of atomic number, something about chemical bonding, and names of some classes of chemical compounds. Where facts come from and how accurately they are known are often…

Ask a physics person what the name of Robert A. Millikan brings to mind, and most would immediately think of the eponymous experiments that he did with the charge on the electron in the years 1908 to 1913. A few might remember his work, starting in 1914, with the experimental determination of Planck's constant using the photoelectric effect. Few…

For physical measurements, the compositions of solutions, especially electrolyte solutions, are expressed in terms of molality rather than mole fractions. The development of the necessary thermodynamic equations directly in terms of molality is not common in textbooks, and the treatment in the literature is not very systematic. We develop a…

The notion that acid salts exist only for diprotic and polyprotic acids is found in many high school and university textbooks, although the "only" condition is not always stated explicitly. A fairly simple experiment shows that there is a pronounced exothermic effect when pure acetic acid is added to potassium acetate. Experiments with similar…

Assuming that textbooks give literary expression to cultural and ideological values of a nation or group, we propose the analysis of chemistry textbooks used in Brazilian universities throughout the twentieth century. We analyzed iconographic and textual aspects of 31 textbooks which had significant diffusion in the context of Brazilian…

How useful are the standard deviations per se, and how reliable are results derived from several least-squares coefficients and their associated standard deviations? When the output parameters obtained from a least-squares analysis are mutually independent, as is often assumed, they are reliable estimators of imprecision and so are the functions…

GEANT4 simulations of the processes affecting the transport and collection of optical photons generated inside a scintillation detector were carried out, with the aim to complement the educational material offered by textbooks to third-year physics undergraduates. Two typical situations were considered: a long scintillator strip with and without a…

Results of a questionnaire survey of 455 two- and four-year institutions on the status on noncalculus physics courses are presented. Responses from 265 questionnaires focus on enrollment, textbooks, reasons for textbook changes, laboratory manuals, and nationally standardized set of laboratory experiments. Selected comments from individual…

As a part of a doctoral thesis considering the history of teaching physical and chemical change, 641 chemistry/science textbooks have currently been examined. These books are from many different countries and date from the eighteenth century to the present time. The books have described a wide variety of experiments to illustrate the difference…