Measuring the acceleration due to gravity g is a part of most introductory physics classes. A standard method to do so is by using a ticker tape timer. However, frictional forces are usually not included in the analysis even though friction leads to an acceleration significantly smaller than "g." In this note, we show how to obtain…

Protein PEGylation refers to the covalent binding of polyethylene glycol (PEG) moieties to a protein and has been increasingly applied, mainly in the biopharmaceutical industry. This technique may increase bioavailability and stability by decreasing immunogenicity and proteolytic attack. Given the industrial interest and the relevance of this…

A new method to determine a ternary phase diagram of benzene-acetic acid-water system is provided to upper-division undergraduate students. The partially miscible liquid phase region can be accurately constructed using isothermal titration microcalorimetry (ITC). Compared with the traditional visual method, ITC can provide precise data and more…

A laboratory class was developed and evaluated to illustrate the synthesis of metal nanoclusters (NCs) and to explain their photoluminescence properties for the case of silver. The described experiment employs a synthetic protocol that consists of two sequential phases in a single reaction pot: the reduction of silver ions into plasmonic silver…

In this article, we describe a fun and engaging card game called Speed Eleusis that teaches the process of scientific discovery and publication, including such practices as replication and retraction. Much like the traditional game of Eleusis and its variant Eleusis Express, this game involves students competing to model a pattern displayed in a…

In 2015, "NFPA 45, Standard on Fire Protection for Laboratories Using Chemicals," from the National Fire Protection Association (NFPA) was updated to include language requiring educators to perform a documented risk assessment when conducting demonstrations in K-12 classrooms. Additionally, in the past five years numerous organizations…

Developing strong safety cultures in academic institutions requires that students at all levels be educated by faculty in chemical safety. Yet chemical safety education is missing from the chemistry curriculum. This article considers a report of numerous injuries from incidents from using flammable chemicals in demonstrations as evidence that…

The Griess assay is widely used by regulation agencies as an official method for nitrite quantification in water and food samples. In Brazil, the official method, which has been used to determine nitrite in food, was described by Instituto Adolfo Lutz (283/IV) in 1984. It uses 8 mL of reactants and provides 50 mL (reactants plus sample) of waste…

The practical two-step synthesis of 1-phenylthiourea is reported here as an undergraduate experiment for the organic synthesis laboratory. The reactions involved in 1-phenylthiourea preparation are very useful didactic examples to illustrate concepts relating to carbonyl substitution and addition, the effect of pH on solubility of organic…

A gamified approach toward Viva voce was implemented in a postlab activity to evaluate students in teams. In a game-show manner, students in teams of three select from an array of anonymized options to reveal a random question. They then chose one member of the team to answer. The assessor evaluated the team by the side instead of facing the…

Surface chemistry impacts technology, advancing the development of new heterogeneous catalysts, semiconductor devices, and materials synthesis. Carbon surfaces are ubiquitous in various fields, and the surface reactivity can be altered by surface functionalization on the molecular scale, introducing functional groups, thus shifting their…

Anatomical sciences curricula have been under constant reform over the years, with many countries having to reduce course hours while trying to preserve laboratory time. In Mexico, schools have historically been autonomous and unregulated, and data regarding structure and methods are still lacking. A national survey was sent by the Mexican Society…

In this work, we made a simple electronic tool called a 'magnetic polarity detector' which can determine the magnetic poles of permanent magnets or electromagnets. We used it in some student experiments in the physics laboratory. For example, determining the magnetic poles of permanent magnets and a current-carrying coils or electromagnets.…

While the three laws of conservation of energy, momentum, and angular momentum are all mentioned in introductory textbooks, there are few experiments through which students can investigate the conservation of angular momentum. Most experiments consist of collisions between rotating disks, in which one disk is dropped on another, or in which the…

Tungsten oxide semiconductors are used to photooxidize water. Students prepare WO3, CuWO4, and mixed composition thin film photoanodes. The syntheses are simple, allowing for the quick production of a range of materials. Photoanodes are tested in a photoelectrochemical cell assembled from common equipment, allowing for the direct comparison of…