Journal Articles: 56 results 

The Penny Experiment Revisited: An Illustration of Significant Figures, Accuracy, Precision, and Data Analysis Joseph Bularzik In this general chemistry laboratory the densities of pennies are measured by weighing them and using two different methods to measure their volumes. The average and standard deviation calculated for the resulting densities demonstrate that one measurement method is more accurate while the other is more precise. Bularzik, Joseph. J. Chem. Educ. 2007, 84, 1456.
Chemometrics 
Nomenclature / Units / Symbols 
Nonmajor Courses 
Physical Properties

Complexometric Titration of Aluminum and Magnesium Ions in Commercial Antacids. An Experiment for General and Analytical Chemistry Laboratories ShuiPing Yang and RueiYing Tsai A novel experiment for determining the total and individual aluminum and magnesium ion content in commercial antacids is described. This experiment is developed with three independent protocols based on complexometric direct and back titrations containing the concepts and usages of blocking, masking, buffer controls and metallic indicators. Yang, ShuiPing; Tsai, RueiYing. J. Chem. Educ. 2006, 83, 906.
Aqueous Solution Chemistry 
Chemometrics 
Consumer Chemistry 
Medicinal Chemistry 
Quantitative Analysis 
Titration / Volumetric Analysis 
UVVis Spectroscopy

Further Analysis of Boiling Points of Small Molecules, CH_{w}F_{x}Cl_{y}Br_{z} Guy Beauchamp Multiple linear regression analysis has proven useful in selecting predictor variables that could significantly clarify the boiling point variation of the CHwFxClyBrz molecules. Beauchamp, Guy. J. Chem. Educ. 2005, 82, 1842.
Chemometrics 
Physical Properties 
Hydrogen Bonding 
Molecular Properties / Structure 
Alkanes / Cycloalkanes

Statistical Comparison of Data in the Analytical Laboratory Michael J. Samide In this article, an experiment designed to provide students with an experience involving statistical treatment of data is described. This experiment allows students to compare 11 different techniques for measuring specific volumes of water. Replicate measurements are taken for each technique and comparisons are made both within a data set and between different data sets. Through calculation of tvalues, students are able to draw conclusions about the precision and accuracy of these various techniques. Samide, Michael J. J. Chem. Educ. 2004, 81, 1641.
Chemometrics

Classification of Vegetable Oils by Principal Component Analysis of FTIR Spectra David A. Rusak, Leah M. Brown, and Scott D. Martin Comparing unknown samples of vegetable oils to known samples using FTIR and principal component analysis (PCA) and nearest means classification (NMC). Rusak, David A.; Brown, Leah M.; Martin, Scott D. J. Chem. Educ. 2003, 80, 541.
IR Spectroscopy 
Instrumental Methods 
Food Science 
Lipids 
Chemometrics 
Qualitative Analysis 
Fourier Transform Techniques 
Consumer Chemistry 
Applications of Chemistry

Precision in Microscale Titration Mono M. Singh, Cynthia B. McGowan, and Zvi Szafran Comparing the precision of a 2mL graduated pipet and 50mL graduated buret in performing a microscale titration. Singh, Mono M.; McGowan, Cynthia B.; Szafran, Zvi. J. Chem. Educ. 2002, 79, 941.
Laboratory Equipment / Apparatus 
Chemometrics 
Microscale Lab 
Titration / Volumetric Analysis

Precision in Microscale Titration Julian L. Roberts Jr. Comparing the precision of a 2mL graduated pipet and 50mL graduated buret in performing a microscale titration. Roberts, Julian L., Jr. J. Chem. Educ. 2002, 79, 941.
Laboratory Equipment / Apparatus 
Chemometrics 
Microscale Lab 
Titration / Volumetric Analysis

Precision in Microscale Titration Julian L. Roberts Jr. Comparing the precision of a 2mL graduated pipet and 50mL graduated buret in performing a microscale titration. Roberts, Julian L., Jr. J. Chem. Educ. 2002, 79, 941.
Laboratory Equipment / Apparatus 
Chemometrics 
Microscale Lab 
Titration / Volumetric Analysis

Experimental Design and Multiplexed Modeling Using Titrimetry and Spreadsheets Peter de B. Harrington, Erin Kolbrich, and Jennifer Cline Determining the acidity of three vinegar samples using multiplexed titrations and an MS Excel spreadsheet. Harrington, Peter de B.; Kolbrich, Erin; Cline, Jennifer. J. Chem. Educ. 2002, 79, 863.
Acids / Bases 
Chemometrics 
Stoichiometry 
Titration / Volumetric Analysis

A Simple Method for Illustrating Uncertainty Analysis Paul C. Yates A fast and simple method for generating data for uncertainty analysis; includes statistical analysis and calculation of maximum probable error for a sample set of data. Yates, Paul C. J. Chem. Educ. 2001, 78, 770.
Chemometrics 
Quantitative Analysis

How Can an Instructor Best Introduce the Topic of Significant Figures to Students Unfamiliar with the Concept? Richard A. Pacer The focus of this paper is how best to introduce the concept of significant figures so that students find it meaningful before a stage is reached at which they become turned off. The approach described begins with measurements students are already familiar with from their life experiences and involves the students as active learners. Pacer, Richard A. J. Chem. Educ. 2000, 77, 1435.
Learning Theories 
Nonmajor Courses 
Chemometrics

Pixel Conversion: A Simple Way to Extract Coordinates of Points from a Printed Graph Christian Aymard and Randall B. Shirts A very simple method is described for extracting the coordinates of points from printed graphs, student reports, or publications. One only needs a flatbed scanner and a desktop computer. This is a convenient and inexpensive alternative to the tedious traditional method using a ruler or to the more costly programs available commercially. A Windows program has been made available to perform the required operations. Aymard, Christian; Shirts, Randall B. J. Chem. Educ. 2000, 77, 1230.
Chemometrics

A Classroom Exercise in Sampling Technique Michael R. Ross A classroom handson demonstration has been developed that looks at the two important sampling considerations, sample size and nonhomogeneous sample materials. This classroom activity makes use of readily available M&M candies for the sample size and NERDS for the nonhomogeneous sample exercises. Ross, Michael R. J. Chem. Educ. 2000, 77, 1015.
Quantitative Analysis 
Chemometrics

Spreadsheet Calculation of the Propagation of Experimental Imprecision Robert de Levie A spreadsheet is used to compute the propagation of imprecision, and a macro is described that will do this automatically. de Levie, Robert. J. Chem. Educ. 2000, 77, 534.
Chemometrics 
Quantitative Analysis 
Laboratory Computing / Interfacing

Precision and Accuracy in Measurements (the author replies) Treptow, Richard S. Relation between instrument resolution and skill. Treptow, Richard S. J. Chem. Educ. 1999, 76, 471.
Chemometrics 
Instrumental Methods

Precision and Accuracy in Measurements Thomsen, Volker The difference between instrument resolution and precision. Thomsen, Volker J. Chem. Educ. 1999, 76, 471.
Chemometrics 
Instrumental Methods

Precision and Accuracy in Measurements: A Tale of Four Graduated Cylinders Richard S. Treptow The concepts of precision and accuracy help students understand that uncertainty accompanies even our best scientific measurements. A model experiment can be used to distinguish the two terms. The experiment uses four graduated cylinders which give measurements of different accuracy and precision. Such terms as mean, range, standard deviation, error, and true value are defined through an illustration. Treptow, Richard S. J. Chem. Educ. 1998, 75, 992.
Quantitative Analysis 
Chemometrics

Precision and Accuracy (the authors reply, 2) Midden, W. Robert Roundingoff rules and significant figures. Midden, W. Robert J. Chem. Educ. 1998, 75, 971.
Chemometrics

Precision and Accuracy (the authors reply, 1) Guare, Charles J. Roundingoff rules and significant figures. Guare, Charles J. J. Chem. Educ. 1998, 75, 971.
Chemometrics

Precision and Accuracy (3) Rustad, Douglas Roundingoff rules and significant figures. Rustad, Douglas J. Chem. Educ. 1998, 75, 970.
Chemometrics

Precision and Accuracy (1) Sykes, Robert M. Standard procedures for determining and maintaining significant figures in calculations. Sykes, Robert M. J. Chem. Educ. 1998, 75, 970.
Chemometrics

A Note on Covariance in Propagation of Uncertainty Edwin F. Meyer It is pointed out that whenever both the slope and the intercept are used in calculating a physical quantity from a linear regression, propagation of error must include the covariance as well as the variances. The point is illustrated with a calculation of the boiling point of water from the parameters of the lnP vs 1/T fit. If the covariance is omitted from the propagation of error, the estimate of uncertainty is unreasonably large. Meyer, Edwin F. J. Chem. Educ. 1997, 74, 1339.
Chemometrics

Buoyancy Programs; Viscosity of Polymer Solutions; Precision of Calculated Values Bertrand, Gary L. Software to simulate the determination of the density of solids; the preparation of polymer solutions and their time to flow through a viscometer; and a program to calculate the uncertainties of results given the input values. Bertrand, Gary L. J. Chem. Educ. 1995, 72, 492.
Physical Properties 
Chemometrics

Measuring with a Purpose: Involving Students in the Learning Process Metz, Patricia A.; Pribyl, Jeffrey R. Constructivist learning activities for helping students to understand measurement, significant figures, uncertainty, scientific notation, and unit conversions. Metz, Patricia A.; Pribyl, Jeffrey R. J. Chem. Educ. 1995, 72, 130.
Nomenclature / Units / Symbols 
Chemometrics 
Constructivism

A Simple Laboratory Experiment Using Popcorn To Illustrate Measurement Errors Kimbrough, Doris R.; Meglen, Robert R. This experiment focuses on the difference between accuracy and precision and demonstrates the necessity for multiple measurements of an experimental variable. Kimbrough, Doris R.; Meglen, Robert R. J. Chem. Educ. 1994, 71, 519.
Chemometrics

Solving equilibria problems with a graphing calculator: A robust method, free of algebra and calculus Ruch, David K.; Chasteen, T. G. The method of successive approximations is frequently introduced in freshman chemistry as a means for solving equilibrium equations. However, this often requires an understanding of calculus that is problematic for introductory chemistry students. An alternative method to solving such equations is to use graphic calculators to solve problems graphically. Ruch, David K.; Chasteen, T. G. J. Chem. Educ. 1993, 70, A184.
Equilibrium 
Chemometrics

Shell thickness of the copperclad cent Vanselow, Clarence H.; Forrester, Sherri R. An exercise in determining the thickness of the copper layer of modern pennies presents the opportunities to combine good chemistry, instrumentation, simple curve fitting, and geometry to solve a simply stated problem. Vanselow, Clarence H.; Forrester, Sherri R. J. Chem. Educ. 1993, 70, 1023.
Metals 
Quantitative Analysis 
Chemometrics

Statistical analysis of errors: A practical approach for an undergraduate chemistry lab: Part 1. The concepts Guedens, W. J.; Yperman, J.; Mullens, J.; Van Poucke, L. C.; Pauwels, E. J. A concise and practiceoriented introduction to the analysis and interpretation of measurement and errors. Guedens, W. J.; Yperman, J.; Mullens, J.; Van Poucke, L. C.; Pauwels, E. J. J. Chem. Educ. 1993, 70, 776.
Chemometrics

Empirical formulas from atom ratios: A simple method to obtain the integer factors of a rational number Weltin, E. Most textbooks advise students to use a method tantamount to trial and error when they encounter a ratio in empirical formula calculations where it is not immediately apparent what the coefficients should be. The author describes a simple procedure that is an effective way to find the integer factors. Weltin, E. J. Chem. Educ. 1993, 70, 280.
Stoichiometry 
Chemometrics

More on the Question of Significant Figures Clase, Howard J. Because so many students have a hard time understanding what significant figures are all about, this author developed a method using "?" to substitute for insignificant zeros. This helps many students finally grasp this convention. Clase, Howard J. J. Chem. Educ. 1993, 70, 133.
Chemometrics

A simple but effective demonstration for illustrating significant figure rules when making measurements and doing calculations Zipp, Arden P. Students can be surprised and confused when different arithmetical operations are performed on experimental data, because the rules change when changing from addition to subtraction to multiplication or division. The following is a simple way to illustrate several aspects of these rules. Zipp, Arden P. J. Chem. Educ. 1992, 69, 291.
Chemometrics

A carbonate project introducing students to the chemistry lab Dudek, Emily A description of a first semester general chemistry laboratory that helps acquaint students with a large variety of chemistry laboratory procedures. Dudek, Emily J. Chem. Educ. 1991, 68, 948.
Chemometrics 
Gravimetric Analysis 
Titration / Volumetric Analysis 
Separation Science

Developmental instruction: Part II. Application of the Perry model to general chemistry Finster, David C. The Perry scheme offers a framework in which teachers can understand how students make meaning of their world, and specific examples on how instructors need to teach these students so that the students can advance as learners. Finster, David C. J. Chem. Educ. 1991, 68, 752.
Learning Theories 
Atomic Properties / Structure 
Chemometrics 
Descriptive Chemistry

Solving quadratic equations to the correct number of significant figures Thomas, Rudolf Presenting an application of the successive approximations method for solving quadratic or higher order expressions. Thomas, Rudolf J. Chem. Educ. 1991, 68, 409.
Equilibrium 
Chemometrics

Is 8C equal to 50F? Thompson, H. Bradford A play, commentary, modest proposal, and a "less modest" proposal regarding calculations and significant figures. Thompson, H. Bradford J. Chem. Educ. 1991, 68, 400.
Chemometrics

A significant example: How many days in a century? Lisensky, George Calculating the number of days in a century can help clarify the subject of significant figures. Lisensky, George J. Chem. Educ. 1990, 67, 562.
Nomenclature / Units / Symbols 
Chemometrics

The acidbase package: A collection of useful programs for protontransfer systems Hawkes, Stephen J. Four programs that deal with the types of acidbase calculations normally encountered in introductory and analytical chemistry courses. Hawkes, Stephen J. J. Chem. Educ. 1989, 66, 830.
Acids / Bases 
Chemometrics

Analysis of kinetic data with a spreadsheet program Henderson, John An article about spreadsheet templates that accept concentration versus time data for several runs of an experiment, determination of leastsquares lines through data points for each run, and will allow the user to exclude points from the leastsquares calculation. Henderson, John J. Chem. Educ. 1988, 65, A150.
Chemometrics 
Laboratory Computing / Interfacing 
UVVis Spectroscopy 
Rate Law 
Kinetics 
Enzymes

Good numerical technique in chemistry: The quadratic equation Thompson, H. Bradford Texts commonly avoid examples with bad roundoff problems or handle them by approximation; none of this is necessary, for simple techniques are available to handle quadratic equations easily and precisely. Thompson, H. Bradford J. Chem. Educ. 1987, 64, 1009.
Chemometrics

The length of a pestle: A class exercise in measurement and statistical analysis O'Reilly, James E. Too many students get through chemistry without acquiring a basic understanding and appreciation of the concepts of measurement science. The purpose of this report is to outline an extremely simple class exercise as a concrete paradigm of the entire process of making chemical measurements and treating data. O'Reilly, James E. J. Chem. Educ. 1986, 63, 894.
Chemometrics

Mathematics in the chemistry classroom. Part 1. The special nature of quantity equations Dierks, Werner; Weninger, Johann; Herron, J. Dudley Differences between operation on quantities and operation on numbers and how chemical quantities should be described mathematically. Dierks, Werner; Weninger, Johann; Herron, J. Dudley J. Chem. Educ. 1985, 62, 839.
Chemometrics 
Stoichiometry 
Nomenclature / Units / Symbols

Propagation of significant figures Schwartz, Lowell M. The rules of thumb for propagating significant figures through arithmetic calculations frequently yield misleading results. Schwartz, Lowell M. J. Chem. Educ. 1985, 62, 693.
Chemometrics

Graphical Analysis, Review II (Dice, David R.) Sievers, Dennis A computerized program that generates graphs of empirical data. Sievers, Dennis J. Chem. Educ. 1984, 61, A324.
Chemometrics

A statistical note on the time lag method for secondorder kinetic rate constants Schwartz, Lowell M. A clever method for finding secondorder kinetic rate constants by using a time lag method that avoids direct measurement of the end point reading P(infinity) can easily be programmed. Schwartz, Lowell M. J. Chem. Educ. 1981, 58, 588.
Chemometrics 
Kinetics 
Rate Law

Teaching and learning problem solving in science. Part I: A general strategy Mettes, C. T. C. W.; Pilot, A.; Roossink, H. J.; KramersPals, H. A systematic approach to solving problems and on designing instruction where students learn this approach. Mettes, C. T. C. W.; Pilot, A.; Roossink, H. J.; KramersPals, H. J. Chem. Educ. 1980, 57, 882.
Chemometrics

Correlating Celsius and Fahrenheit temperatures by the "unit calculus" Gorin, George Deriving the mathematical relationship between Celsius and Fahrenheit temperatures. Gorin, George J. Chem. Educ. 1980, 57, 350.
Nomenclature / Units / Symbols 
Chemometrics

Adopting SI units in introductory chemistry Davies, William G.; Moore, John W. Conventions associated with SI units, conversion relationships commonly used in chemistry, and a roadmap method for solving stoichiometry problems. Davies, William G.; Moore, John W. J. Chem. Educ. 1980, 57, 303.
Nomenclature / Units / Symbols 
Chemometrics

Measurement errors: A lecture demonstration Munn, Robert J. A lecture demonstration to realistically discuss precision, accuracy, averaging, data rejection, and significant digits. Munn, Robert J. J. Chem. Educ. 1979, 56, 267.
Chemometrics

How many significant digits in 0.05C? Power, James D. Textbooks abound with erroneous examples, such as 33F = 0.56C. Power, James D. J. Chem. Educ. 1979, 56, 239.
Chemometrics 
Nomenclature / Units / Symbols

Significant digits in logarithmantilogarithm interconversions Jones, Donald E. Most textbooks are in error in the proper use of significant digits when interconverting logarithms and antilogarithms. Jones, Donald E. J. Chem. Educ. 1972, 49, 753.
Nomenclature / Units / Symbols 
Chemometrics

Chemical exponentialism for beginners Larson, G. Olof Presents a method for introducing and reviewing exponential mathematical operations. Larson, G. Olof J. Chem. Educ. 1970, 47, 693.
Chemometrics

The significance of significant figures Pinkerton, Richard C.; Gleit, Chester E. This paper is an attempt to clarify some of our ideas about numerical data, measurements, mathematical operations, and significant figures. Pinkerton, Richard C.; Gleit, Chester E. J. Chem. Educ. 1967, 44, 232.
Nomenclature / Units / Symbols 
Chemometrics

Statistical analysis of data in the general chemistry laboratory Chapin, Earl C.; Burns, Richard F. Students are asked to analyze data collected with respect to determinations of Dumas molecular weight, equivalent weight of a metal, equivalent weight of an acid, and molecular weight by freezing point depression. Chapin, Earl C.; Burns, Richard F. J. Chem. Educ. 1965, 42, 564.
Chemometrics

A method of visual representation of three dimensional functions Lemlich, Arthur; Zinsser, Hans H. Lego blocks are used to visually represent threedimensional functions. Lemlich, Arthur; Zinsser, Hans H. J. Chem. Educ. 1964, 41, 165.
Chemometrics 
Mathematics / Symbolic Mathematics

A formula for indirect gravimetry Fiekers, B. A. Derivation of a formula for indirect gravimetry and application to a sample problem. Fiekers, B. A. J. Chem. Educ. 1956, 33, 575.
Gravimetric Analysis 
Chemometrics 
Quantitative Analysis

The experimental determination of an error distribution Nelson, Lloyd S. Discusses an experiment in which students are asked to the average deviation and probable errors in their measurements. Nelson, Lloyd S. J. Chem. Educ. 1956, 33, 126.
Chemometrics

