S P R I N G 1 9 9 8


Bulletin Board
Course Guide
Exam Guide


©1997 by
F. A. Senese

Resources for analytical chemistry students

Data Analysis
General references


A concise reference to the Metric System (SI) (David Bartlett)
In addition to the tables of prefixes and derived units, this page includes a brief history of the SI system and the physical basis for the base units. It also includes tips on correct usage of the SI (e. g. a billion in the US is not the same as a billion in the UK!) (9/09/98)

Conversion Factor Calculator (Process Associates of America)
Unit conversion calculators for many different fundamental physical quantities.

Dictionary of Measures, Units, and Conversions (Frank Tappan, University of Exeter)
This dictionary includes most units in common use, along with SI conversions. Units are listed both by category (length, energy, pressure, etc.) and alphabetically. The dictionary includes historical notes, descriptions of the metric system, the U K (Imperial) system with a statement on the implementation of 'metrication' in the U K, and the U S system. (7/24/98)

Good Enough For Chemistry (Brad Thompson)
Thompson's "tragedy in three parts" dramatizes the consequences of blindly following the rules of thumb for propagating significant figures through calculations. (11/18/99)

How Many? A Dictionary of Units (Russ Rowlett, University of North Carolina)
From abamperes to zollen, Rowlett's dictionary gives meanings, abbreviations, derivations, conversion factors, and definitions for hundreds of units of measure. Brief primers on international, mks, cgs, and English measurement systems and a bibliography round out the site. (8/12/99)

Mass, Volume, and Density (MathMol Project, NYU)
An interactive review of basic mass, volume, and density relationships and measurements, including challenge problems. (10/27/99)

Measurement Uncertainty at Low Concentrations (Wolfhard Wegscheider, Univ. of Loeben)
"At low concentrations the relative uncertainty increases to the point where it is no longer pertinent to refer to a quantitative result (limit of determination) and - yet lower - to a point where the signal is not recognizable against the noise (limit of detection). It is shown in this contribution how measurement uncertainty can be linked to the limit of determination for various analytical procedures described in the EURACHEM Guide. " (07/26/00)

Measurement! (The Numeracy Center)
The Numeracy Center's Measurement! site is a light treatment of a very dry subject. In addition to the usual background on measurement, significant figures, and the SI system, the authors include several interesting problems that involve critical thinking ("Does this data support the contention that the average Australian will be 1.93 m (6' 3") by 2060?), practical problem solving ("Could the accused really have escaped with that amount of gold in their briefcases?") and some bad jokes that make good points. (11/27/98)

Orders of magnitude: Distance (Erik Max Francis)
A graphic that illustrates the sizes of SI system prefixes using objects and distances ranging in size from the proton to the radius of the observable universe. (7/29/98)

Powers of Ten (Dept. of Physics & Astronomy, Arizona State University)
An introduction to SI prefixes and arithmetic with exponential notation. Part of an online physical science course "Patterns in Nature". Unfortunately the assignment and exercise links are not functional. (8/25/99)

The NIST Reference on Constants, Units, and Uncertainty (Physics Laboratory, NIST)
The Physics Laboratory at The National Institute of Standards and Technology (NIST) website provides several excellent resources, including a table of physical constants with a searchable bibliography, in-depth information on the SI system, and guidelines for the expression of uncertainty in measurement. The site is written for a professional audience; general chemistry students may find some of the terminology and notation difficult. Some documents require the Adobe Acrobat plugin. (8/25/99)

The Origin of the Celsius Temperature Scale (Johan and Ann Santesson)
A summary of Anders Celsius's 1742 paper "Observations on two persistent degrees on a thermometer", which describes the rationale and origins of the Celsius temperature scale. (11/14/98, 10/13/00)

Data analysis

Chemometrics (James Hardy, University of Akron)
Chemometrics is a branch of analytical chemistry that applies mathematical, statistical, and computational techniques to help interpret very complex experimental data like spectra and chromatograms. This site contains PowerPoint lecture slides for Hardy's course in chemometrics at the University of Akron. (12/27/98)


Chemical Reaction Stoichiometry (R. W. Missen and W. R. Smith, University of Guelph)
Some reactions are nearly impossible to balance using the simple methods we've outlined in this course. Problems arise when the number of unknowns (the stoichiometric coefficients) isn't equal to the number of independent equations (one mass balance equation for each element present, and a charge balance equation). Drs. Missen and Smith examine the problem of balancing chemical equations from a mathematical (rather than trial-and-error or recipe-oriented) point of view. The payoff is a procedure for balancing equations that is completely general and easy to program. The site includes a Java applet that implements their algorithm. (8/12/98)

Limiting reagents (Carnegie-Mellon University)
An interactive bar graph is used to show how reactant and product amounts change over the course of a chemical reaction. (7/23/98)


All About Chemical Equilibrium (Stephen Lower, Simon Fraser University)
A well-written introduction to chemical equilibrium, Le Chatelier's principle, reaction quotients, equilibrium constants, the law of mass action, and equilibrium calculations, with many worked examples that help tie the material to practical applications. (03/03/02)

General references

Antoine Equation (
A JavaScript calculator that estimates vapor pressure for a few common materials using the Antoine equation. (4/11/99)

CRC Handbook of Chemistry and Physics (CRC Press)
This quintessential handbook contains data for about 2500 inorganic compounds and 12000 organic compounds. Relevant physical properties listed include crystal structure, color, solubility, melting points, boiling points, heats of formation, heats of vaporization, heats of fusion, entropies, heat capacities, critical pressure and temperature, vapor pressure, and optical properties. (Book/CDROM; no Web access). (12/12/98)

CS Chemfinder (Cambridge Software)
Chemfinder is the most comprehensive resource for chemical compound data on the Web at this time. Enter the formula, name, molecular weight, or even a drawn structure fragment of a compound and this database fills in the blanks and returns structural formulas and a few other properties, along with compound-specific MSDS links. The database presently contains over 75000 compounds, although detailed data is available only for a few thousand of the most common compounds. Cambridge provides a free browser plugin that allows you to draw the molecular structure you're searching for in the browser window. If you find yourself using the database regularly, the site will require you to register (registration is free). Searches are (quite reasonably) restricted for bandwidth considerations. A commercial version of the database doesn't have these restrictions. (7/25/98)

Engineering Material Properties (Apache Point Observatory)
A table of properties for common materials, including densities, heat capacities, heats of combustion, heats of vaporization, heats of fusion, thermal conductivities, thermal expansion coefficients, viscosities, and more. (9/19/98)

MatWeb: The Free Online Materials Properties Database (Automation Creations, Inc.)
A growing database of properties of industrial materials, including densities and other physical properties, as well as mechanical, thermal, and electrical properties. (7/25/98)

Metal Alloy Properties Data (Principal Metals)
A comprehensive, searchable database containing material property and composition data for more than 5000 metal alloys. (01/26/00)

NIST Atomic Spectroscopic Database (National Institute of Standards and Technology)
Energy levels, transition probabilities, and wavelengths for atomic line spectra. Ionization energies for neutral atoms are also available on a hyperlinked periodic table. (7/25/98)

NIST Chemistry WebBook (National Institute of Standards and Technology)
Property and spectral data for elements, organic compounds, and small inorganic compounds can be retrieved by chemical formula, name, partial formula, CAS registry number, molecular weight, or by thermochemical properties. The database includes thermochemical data (enthalpies, entropies, heat capacities, ...) for several phases and for reactions and phase transitions, ion energetics data (ionization energies, electron affinities, ...) and spectroscopic information (IR, UV, visible, and mass spectra). (7/25/98)

Properties of Gases and Liquids (R. C. Reid, J. M. Praunitz, B. E. Poling)
This handbook provides models and parameters for estimating thermodynamic properties of gases and liquids, both pure and mixtures, including enthalpies, entropies, fugacity coefficients, heat capacities, and critical points; vapor-liquid and liquid-liquid equilibria. ISBN: 0070517991, published by McGraw-Hill. (4/11/99)

Thermo Explorer (SEA++, Octavian Micro Development)
A "chemical engineering calculator" that searches a database of 600 common compounds to give boiling points, melting points, critical points, dipole moments, liquid densities, and plots of vapor pressure and heat capacity over specific temperature ranges. (7/25/98)

Thermo Properties Page (Quest Consultants, Inc.)
Select a pure substance or a mixture from a list of about 300 compounds to calculate liquid and vapor densities, enthalpies, heat capacities, and compositions at an input temperature and pressure. Calculations are based on the empirical Peng-Robinson equation of state. You can calculate dew points, bubble points, enthalpy-pressure diagrams, and pressure-volume diagrams by following links on the bottom of the page. (11/19/99)

Vapor Pressures of Pure Substances (Bernhard Spang)
A brief introduction to the Antoine equation, used to estimate the vapor pressure of substances as a function of temperature. Includes Antoine equation parameters for selected substances. (4/11/99)

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Last Revised 02/04/99.
Copyright © 1999 by F. Senese. All Rights Reserved.