TIGER

Other Resources: 43 results
Molecular Models of EDTA and Other Chelating Agents  William F. Coleman
Deirdre Bell-Oudry presents a variation on an old theme in her paper on using an indirect EDTA titration for sulfate analysis (1). EDTA and (often loosely) related species are this month's Featured Molecules.EDTA is a hexaprotic acid (H6Y2+) having the pKa values given in the featured paper (1). Figure 1 shows a distribution diagram for the EDTA system (2). At the pH of normal waters, the predominant species have one or both of the nitrogen atoms protonated.Complexation, however, requires that both nitrogens be deprotonated and it is generally assumed that the form that complexes with metal ions is Y4−. Structures of several forms of EDTA are included in the molecule collection (Figure 2). These structures are quite flexible having many conformations that are readily accessible at room temperature.An introduction to EDTA chemistry leads to broader questions of metal ion chelation or sequestration. Related chelating agents included in the molecule collection are EGTA, DCTA, NTA, BAPTA, and DTPA. Molecular dynamics and Hartree-Fock calculations on BAPTA (Figure 2) confirm that many conformations, ranging from those with the phenyl rings parallel to one another, to more elongated forms, are essentially isoenergetic in room temperature aqueous solution (3).Also included in the molecule collection are several crown ethers, an isophore (nonactin), and a cryptand. These not only provide students with a glimpse of the types of molecules being employed for metal ion sequestration but open a wide range of topics of current research in a variety of areas of inorganic, industrial, environmental, and biological chemistry.
Aqueous Solution Chemistry
Hydration of Ions  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Aqueous Solution Chemistry
Conjugate Acid-Base Pairs and pH  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Aqueous Solution Chemistry
Ammonia (GCMP)  David M. Whisnant
Ammonia fountain: this is a resource in the collection "General Chemistry Multimedia Problems". In an ammonia fountain, a flask is filled with ammonia gas. A tube from the flask extends into a pan of water that contains phenolphthalein. When a rubber bulb full of water is squeezed, the water squirts into the flask. Water from the pan then is pushed into the flask and the indicator changes color. General Chemistry Multimedia Problems ask students questions about experiments they see presented using videos and images. The questions asked apply concepts from different parts of an introductory course, encouraging students to decompartmentalize the material.
Acids / Bases |
Aqueous Solution Chemistry
The Nobel Prize and Aqua Regia  Robert Hetue
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Aqueous Solution Chemistry |
Precipitation / Solubility
Ionic Equilibria in Aqueous Solutions in Foods  Sofia Erazo
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Equilibrium |
Nutrition |
Aqueous Solution Chemistry
Buffer Solutions  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Acids / Bases |
Aqueous Solution Chemistry
Hydrogen and Hydroxide Ions  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Aqueous Solution Chemistry |
Water / Water Chemistry
Chromate-Dichromate (GCMP)  David M. Whisnant
Chromate/Dichromate: this is a resource in the collection "General Chemistry Multimedia Problems". In this problem we will study shifts in the equilibrium between chromate and dichromate. General Chemistry Multimedia Problems ask students questions about experiments they see presented using videos and images. The questions asked apply concepts from different parts of an introductory course, encouraging students to decompartmentalize the material.
Oxidation / Reduction
Halogens and Halides (GCMP)  David M. Whisnant
Halogens and Halides: this is a resource in the collection "General Chemistry Multimedia Problems". In this problem we will study the oxidation-reduction reactions between the halogens and the halide ions. The halogens and halides will be dissolved in water and hexane. General Chemistry Multimedia Problems ask students questions about experiments they see presented using videos and images. The questions asked apply concepts from different parts of an introductory course, encouraging students to decompartmentalize the material.
Oxidation / Reduction
Redox Reactions  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Oxidation / Reduction
Balancing Redox Equations  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Oxidation / Reduction
Common Oxidizing Agents  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Oxidation / Reduction
Redox Couples  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Oxidation / Reduction
Introduction of Aquatic Chemistry in General Chemistry Curriculum;Spreadsheet Calculation Approaches  Chulsung Kim
Fundamental aquatic chemistry concepts may be introduced in general chemistry classes by computing ionization fractions and buffer intensity of aqueous phase carbonate systems. This Excel spreadsheet may used to build graphic presentations of a titration curve, distribution diagram, and buffer intensity as a function of pH. Accompanying activities are designed to enhance the concepts of acid-base equilibrium through exploring the relationship between pKa/pKb, pH of the solution, ionization fractions, and buffer intensity, and to exercise students graphing skills.
Acids / Bases |
Aqueous Solution Chemistry |
pH |
Titration / Volumetric Analysis |
Water / Water Chemistry |
Equilibrium
A Greener Bleach  Stacy Gates
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Oxidation / Reduction |
Green Chemistry
Corrosion in Astronomy  Robert Hetue
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Oxidation / Reduction |
Metals |
Astrochemistry
Common Reducing Agents  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Metals |
Oxidation / Reduction
Substances Which Are Both Oxidizing and Reducing Agents  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Oxidation / Reduction |
Water / Water Chemistry
Corrosion  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Electrolytic / Galvanic Cells / Potentials |
Oxidation / Reduction
Netorials  
The Netorials cover selected topics in first-year chemistry including: Chemical Reactions, Stoichiometry, Intermolecular Forces, Acids & Bases, Biomolecules, and Electrochemistry.
Acids / Bases |
Stoichiometry |
Proteins / Peptides |
Enzymes |
Carbohydrates |
Nucleic Acids / DNA / RNA |
Lipids |
Oxidation / Reduction |
Noncovalent Interactions
General Chemistry Multimedia Problems  David M. Whisnant
General Chemistry Multimedia Problems ask students questions about experiments they see presented using videos and images. The questions asked apply concepts from different parts of an introductory course, encouraging students to decompartmentalize the material.
Acids / Bases |
Atomic Spectroscopy |
Calorimetry / Thermochemistry |
Isotopes |
Magnetic Properties |
Phases / Phase Transitions / Diagrams |
Surface Science |
Thermodynamics |
Equilibrium |
Oxidation / Reduction
The Reaction Rolodex; A Web-Based System for Learning Reactions in Organic Chemistry  Eric Mahan
This Web-based system of note cards has been developed to aid students in learning the vast number of reactions encountered in organic chemistry. A thorough knowledge of these reactions is essential for success in first- and second-semester organic chemistry courses. The reactions are organized by functional group and can be chosen from a menu at the left side of the Web page. Once a particular reaction has been selected, the main frame displays the reactant(s) and reagent(s) along with a question mark in place of the product. After considering the reaction as long as needed, the user can click the question mark to reveal the reaction product. Clicking the product will again hide the answer and regenerate the question mark so that the reaction can be practiced again. Selecting other reactions from the menu on the left allows them to be practiced in the same manner.
Reactions
Chemical Reactions (Netorials)  Rachel Bain, Mithra Biekmohamadi, Liana Lamont, Mike Miller, Rebecca Ottosen, John Todd, and David Shaw
Chemical Reactions: this is a resource in the collection "Netorials". The Netorials cover selected topics in first-year chemistry including: Chemical Reactions, Stoichiometry, Thermodynamics, Intermolecular Forces, Acids & Bases, Biomolecules, and Electrochemistry.
Reactions
Spontaneous Processes and Molecular Probability  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Reactions
Rates of Spontaneous Processes  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Reactions
What Chemists Do  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Reactions
Chemical Reactions  American Chemical Society
ACS Science for Kids activities exploring chemical reactions.
Reactions
Energy and the Formation of Ions  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Reactions |
Thermodynamics
Le Chatelier's Principle  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Reactions |
Equilibrium
The Effect of a Change in Pressure  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Reactions |
Equilibrium
Alcohols  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Alcohols |
Addition Reactions
Named Reactions  Michael B. Smith
This Web site lists 95 of the most important named reactions in organic chemistry. Each is linked to a Web page that gives the primary reference and equations for one or more recent literature examples that illustrate the use of the reaction.
Nomenclature / Units / Symbols |
Reactions
Named Reagents  Hans J. Reich
This convenient list provides structures of more than 160 common reagents used in organic chemistry that are often referred to by the originator's name, by an acronym, or by a trade name.
Nomenclature / Units / Symbols |
Reactions
Bond Enthalpies and Exothermic or Endothermic Reactions  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Calorimetry / Thermochemistry |
Reactions
The Effect of Temperature  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Reactions |
Kinetic-Molecular Theory
Macroscopic and Microscopic Views of a Chemical Reaction  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Reactions |
Molecular Properties / Structure
Building  American Chemical Society
ACS Science for Kids activities exploring the chemistry behind building many everyday objects and structures.
Industrial Chemistry |
Physical Properties |
Reactions |
Consumer Chemistry
Chemical & Physical Change  American Chemical Society
Everything you see and touch has the ability to change. Sometimes substances change to form new substances. This is called a chemical change. Other times substances change but keep the same identity. This is called a physical change. Try these activities to learn more about chemical and physical change.
Acids / Bases |
Reactions |
Water / Water Chemistry |
Solutions / Solvents |
Consumer Chemistry
Graphing  American Chemical Society
ACS Science for Kids activities explore the aspects of recording scientific data and presenting that data in useful graphs.
Reactions |
Chemometrics |
Physical Properties |
Transport Properties |
Plant Chemistry
Toys-ACS Science for Kids  American Chemical Society
ACS Science for Kids activities explore how chemistry can be used to make toys.
Gases |
Polymerization |
Water / Water Chemistry |
Physical Properties |
Lipids |
Reactions
Air-Solids, Liquids & Gases  American Chemical Society
ACS Science for Kids activities explore the properties of gases.
Atmospheric Chemistry |
Acids / Bases |
Reactions |
Applications of Chemistry |
Water / Water Chemistry |
Gases
Characteristics of Materials  American Chemical Society
What makes diapers absorbent? Is peanut butter stickier than syrup or jelly? Strong, stretchy, sticky, or sweet—everything around us has special properties which make them unique. See if you can identify and compare the characteristics of materials.
Industrial Chemistry |
Physical Properties |
Reactions |
Consumer Chemistry |
Gases |
Carbohydrates |
Proteins / Peptides |
Crystals / Crystallography |
Water / Water Chemistry |
Plant Chemistry |
Dyes / Pigments |
Lipids |
Molecular Properties / Structure |
Applications of Chemistry |
Nutrition |
Acids / Bases |
Chromatography |
Magnetic Properties |
Metals |
Polymerization |
Solutions / Solvents |
Descriptive Chemistry |
Food Science