Undergraduate Chemistry Laboratory Research Articles

An Online Booking System Encourages Self-Directed Learning and Personalization of Study

Collaboration between the chemistry and computing services departments was undertaken to create an online booking system to be used as a learning and teaching aid in an undergraduate chemistry lab course. The system helped promote personalization of study and could be easily adapted to any department within the university. The system was implemented in a number of educational contexts, which are discussed, along with an evaluation of the system. Students easily adapted to the new process with a high percentage appreciating the freedom it offered. We hope that other universities will consider similar collaborations within their own institutions as pedagogical research strongly suggests that introducing certain levels of flexibility into courses encourages active learning and enhances student engagement.

Student Outcomes from Innovations in Undergraduate Chemistry Laboratory Learning.

Much of the research on implementation of novel curriculum, instruction, and assessment in undergraduate science laboratory courses in the U.S. has been funded by public funding agencies. A review and analysis was conducted of awards made between 2000 and 2008 from the National Science Foundation that have focused on laboratory learning in undergraduate chemistry. The study is concerned with characterizing the types of interventions that occurred, and what was studied and learned related to student learning and associated outcomes. For projects that concluded by August, 2011, an overview is presented of the current ‘state of the art’ of the empirical knowledge base, in the interest of suggesting gaps and opportunities for further study. The findings are also contrasted with a recent summary of the state of chemical education research, largely focused at undergraduate level teaching and learning, that was presented in a review paper commissioned by the National Academies of Science as part of a consensus study on discipline-based education research.

Simple and Low Cost Polarimeter System

Fundamental wave properties of light are wavelength, frequency, propagation direction, and polarization. In order to understand the polarization behavior of light as well as the polarization change during light matter interaction, we propose a simple multi point measurement system based on phase change. This system offers data acquisition and signal processing with computer at basic level which are substantial for multidisciplinary studies. This system could be used in undergraduate level physics and chemistry laboratories to teach the students the polarization dynamics in a simplified and practical way. Here in this paper, we utilized this system in order to measure the optical activities of glucose.

Biomimetic oxidation of carbamazepine with hydrogen peroxide catalyzed by a manganese porphyrin

This laboratory project is planned for an undergraduate chemistry laboratory in which students prepare a manganese porphyrin able to mimic the oxidative metabolism of carbamazepine, one of the most frequently prescribed drugs in the treatment of epilepsy. The in vitro oxidation of carbamazepine results in the formation of the corresponding 10,11-epoxide, the main in vivo metabolite. The reaction is catalyzed by manganese porphyrin in the presence of H2O2, an environmentally-friendly oxidant. Through this project students will develop their skills in organic synthesis, coordination chemistry, chromatographic techniques such as TLC and HPLC, UV-visible spectrophotometry, and NMR spectroscopy.

Improving the school-to-university transition: using a problem-based approach to teach practical skills whilst simultaneously developing students' independent study skills

Despite being criticised for placing little emphasis on thinking, the majority of laboratory work at school level is taught via expository ‘recipe-style’ labs. This has been seen to result in students struggling to be able to apply the practical techniques they have learnt in the classroom outside the narrow environment in which they were taught. This paper describes the design, trial and evaluation of a collection of ten practical activities which use a problem-based approach to laboratory instruction to deepen the students' understanding of the standard laboratory techniques they would be expected to know on entering an undergraduate chemistry laboratory. The practical activities have been trialled by over 100 students in eight different schools and feedback obtained via student questionnaire and informal comments provided by teachers. Compared to typical laboratory instruction, the students find the problem-based practical activities more interesting and better for making them think. Over 80% of the students indicate that the problem-based activities are ‘good’ or ‘very good’ for the application of practical techniques. Furthermore, the problem-based practical activities scored favourably compared to a typical laboratory activity for developing the students' independent study skills, team working and communication skills, scientific writing and research skills.

A Unit Cell Laboratory Experiment: Marbles, Magnets, and Stacking Arrangements

An undergraduate first-semester general chemistry laboratory experiment introducing face-centered, body-centered, and simple cubic unit cells is presented. Emphasis is placed on the stacking arrangement of solid spheres used to produce a particular unit cell. Marbles and spherical magnets are employed to prepare each stacking arrangement. Packing efficiency is calculated using simple measurements of marble or magnet diameters and the dimensions of the stacking arrangement. Edge effects are introduced. Packing efficiency is subsequently calculated for various metal samples employing density measurements and literature atomic radii values. The stacking arrangement for each metal and its corresponding unit cell are determined by comparing packing efficiency values. Estimated percent unoccupied space values for water and air are also determined.

Argument-Driven Inquiry: An Introduction to a New Instructional Model for Use in Undergraduate Chemistry Labs

This article presents a new instructional model called Argument-Driven Inquiry (ADI) that can be used in undergraduate college chemistry laboratory courses. ADI is designed to provide students with an opportunity to develop their own method to generate data, to carry out investigations, use data to answer research questions, write, and be more reflective as they work. In addition, the ADI instructional model integrates opportunities for students to engage in scientific argumentation and peer review. This article describes the ADI instructional model, provides the empirical and theoretical foundation for it, and presents a detailed semester pacing schedule for general chemistry I laboratories, peer-review guides, and instructor scoring rubrics.

Laboratory Experiment on Electrokinetic Remediation of Soil

Electrokinetic remediation is a method of decontaminating soil containing heavy metals and polar organic contaminants by passing a direct current through the soil. An undergraduate chemistry laboratory is described to demonstrate electrokinetic remediation of soil contaminated with copper. A 30 cm electrokinetic cell with an applied voltage of 30 V is used to demonstrate the redistribution of copper in sand initially contaminated with 0.24 M copper chloride solution. The copper content in sand is measured by acid extraction followed by complexometric titration. The measurement of the pH across the cell is used to demonstrate the difference in mobility between the H+ and OH– ions during the electrokinetic process.

Measurement of the Compressibility Factor of Gases: A Physical Chemistry Laboratory Experiment

In this article, we describe an experiment for the undergraduate physical chemistry laboratory in which students measure the compressibility factor of two gases, helium and carbon dioxide, as a function of pressure at constant temperature. The experimental apparatus is relatively inexpensive to construct and is described and diagrammed in detail. Students analyze their data to determine values for the second virial coefficient for each gas, which may then be compared with the literature. The experiment demonstrates the nonideality of real gases.

A Portable, Low-Cost, LED Fluorimeter for Middle School, High School, and Undergraduate Chemistry Labs

A low-cost portable fluorimeter was constructed using a 360 nm LED for excitation and a silicon photodiode for detection. The instrument is simple to operate and has been used to investigate fluorescent whitening agents extracted from various brands of paper, to determine the linear range and limit of detection of quinine in various commercial tonic water samples, and to quantify the amount of vitamin B1 in commercial multivitamin supplements. The instrument is straightforward to construct and to use and facilitates the introduction and hands-on application of spectroscopy, fluorescence, and related topics in middle school, high school, and undergraduate laboratory courses.

Development of an electronic nose sensing platform for undergraduate education in nanotechnology

The teaching of the different aspects of a sensor system, with a focus on the involved nanotechnology, is a challenging, yet important task. We present the development of an electronic nose system that utilizes a nanoscale amperometric sensing mechanism for gas mixtures. The fabrication of the system makes use of a basic microfabrication facility, as well as an undergraduate chemistry laboratory for material synthesis and preparation. The sensing device consists of an array of cross-reactive sensors composed of metal-oxide semiconducting nanoparticles. Each sensor in the array produces a unique response in the presence of a target gas, allowing the sensor to determine the identity and concentration of multiple gases in a mixture. The educational aspects include microheater simulation and fabrication, design and fabrication of interdigitated electrodes, development of interfacing circuitry and software, development and calibration of a sensory array, sol–gel processing of nanoparticle films and their characterization, and details of the fundamental chemical sensing mechanism.

Molecular Iodine Fluorescence Using a Green Helium−Neon Laser

Excitation of molecular iodine vapor with a green (543.4 nm) helium−neon laser produces a fluorescence spectrum that is well suited for the upper-level undergraduate physical chemistry laboratory. Application of standard evaluation techniques to the spectrum yields ground electronic-state molecular parameters in good agreement with literature values. The use of a green helium−neon laser provides advantages in data collection, data analysis, cost, and safety relative to other I2 excitation sources.

A Global Perspective on the History, Use, and Identification of Synthetic Food Dyes

This article presents a brief history of the artificial coloration of foods, a discussion of the worldwide use of synthetic food dyes, and methods for separating and identifying 14 dyes in common use globally. The United States Food and Drug Administration presently has certified seven synthetic dyes for use in foods. An additional seven synthetic dyes are commonly found in foods in other parts of the world. The structures of these 14 dyes, as well as their separation by paper chromatography and identification by visible absorption spectroscopy are discussed. Also included are specific ideas on how to incorporate experiments involving synthetic food dyes into the undergraduate chemistry laboratory curriculum.

Optical Sensors for Manual and Automatic Titration in Undergraduate Laboratory

ABSTRACT The classic undergraduate titration analysis is upgraded using instrumental detection of end point with color indicators. Several color sensors (CCD-based spectrophotometer, video camera with RGB digitalization, photodiode with appropriate filters) were tested in order to replace the visual indication of the end point with different indicators. The developed procedures show adequate characteristics such as a short titration time and accuracy of 0.1–1%. Specific features of particular titrations such as hardness of water and argentometric titration of chloride are discussed. In the author's opinion, this experimental setup represents an affordable ($100-level) option for an undergraduate or advanced high school chemistry laboratory.

Gunshot Residue Analysis in the Undergraduate Laboratory Using Toy Cap Guns

ABSTRACT The authors developed an experiment for the undergraduate analytical or forensic chemistry laboratory in which gunshot residues (GSRs) produced from toy cap guns are analyzed by laser-induced breakdown spectroscopy (LIBS). Alternatively, the experiment is readily adaptable to any emission spectroscopy technique. This project allows students to investigate the development of a forensic method while addressing proper sampling techniques used in forensic investigations. Students were able to develop a library of blank samples, establish signal detection limits to address legal considerations for determination of false-positive and -negative error rates, and optimize an emission spectrometer.

Faculty Perspectives of Undergraduate Chemistry Laboratory: Goals and Obstacles to Success

Faculty perspectives of the undergraduate chemistry laboratory were the focus of a study to articulate the goals, strategies, and assessments used in undergraduate teaching laboratories. Data were collected via semistructured interviews with faculty (N = 22) from community colleges, liberal arts colleges, comprehensive universities, and research institutions engaged in teaching or supervising undergraduate laboratories. The goals for general chemistry, organic chemistry, and upper-division laboratories are described and compared among faculty who have received NSF-CCLI (now called NSF-TUES) grants to implement changes in laboratory and those who have not. Problems and limitations to success in laboratory are also reported, and the impact of these obstacles on student achievement and laboratory curricula is discussed.

Thermochemistry to the Rescue: A Novel Calorimetry Experiment for General Chemistry

A novel calorimetry experiment that (i) provides “real-world” connections, (ii) assists students in learning thermochemistry, and (iii) uses equipment commonly found in an undergraduate general chemistry laboratory was implemented at our institution. Ultimately, students design a custom heat pack to treat the frostbitten hand of an Alaskan pipeline maintenance worker. First, students measure and use the specific heat of Vienna sausage to approximate the hand’s specific heat. Students obtained a mean specific heat of 3.1 ± 0.5 J g−1 °C−1 for Vienna sausage, which compares favorably with generally accepted values for the human body’s specific heat. Second, students qualitatively determine heats of salt dissolution and identify a salt for their heat pack. Next, students quantitatively determine their chosen salt’s heat of dissolution. Finally, using the Vienna sausage’s specific heat, students estimate the heat required to raise the temperature of the hand from 15 °C (frostbite risk) to 37 °C, calculate the ...

Excited-State Processes in Slow Motion: An Experiment in the Undergraduate Laboratory

Lasers have transformed chemistry and the everyday world. Therefore, it is not surprising that undergraduate chemistry students are frequently exposed to fairly advanced laser techniques. The usual topics studied with lasers are molecular spectroscopy and chemical kinetics. Static and dynamic fluorescence experiments seem to be particularly popular. The phenomenon of phosphorescence, on the other had, has received much less attention in the undergraduate physical chemistry laboratory. A few years ago, we developed a laser experiment that introduced students to the phosphorescence quenching of the carbazole−naphthalene system under steady-state and pulse-excitation conditions. The purpose of that experiment was to demonstrate the experimental and theoretical aspects of triplet−triplet nonradiative energy transfer between two aromatic molecules. Subsequently, we modernized the experiment by introducing an inexpensive and easy-to-use Ocean Optics data acquisition system. This not only greatly simplified the experiment, but also made it more accessible to students. This article presents the upgraded version of the experiment together with suggestions for practical implementation.

Correction to Personal Multifunctional Chemical Analysis Systems for Undergraduate Chemistry Laboratory Curricula

Correction to Personal Multifunctional Chemical Analysis Systems for Undergraduate Chemistry Laboratory Curricula

Chemical Vapor Deposition of Aluminum Oxide Thin Films

Chemical vapor deposition (CVD) is a process routinely used to produce thin films of materials via decomposition of volatile precursor molecules. Unfortunately, the equipment required for a conventional CVD experiment is not practical or affordable for many undergraduate chemistry laboratories, especially at smaller institutions. In an effort to expose undergraduate chemistry students to this valuable materials science technique, a convenient, inexpensive apparatus was constructed to deposit thin films of aluminum oxide on a silicon wafer substrate. The system features the controlled hydrolysis of the water-sensitive precursor liquid, dimethylaluminumisopropoxide, at 200 °C. The experiment described herein is customizable depending on the resources available and lends itself to an inquiry-based format. A discussion of overall student sentiment and pedagogical outcomes from this module is also included.