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Other Resources: 19 results
ChemPaths 104 W Apr 6  John W. Moore
Today in Chem 104: * Lecture: Bronsted Acids and Bases * Reading: Kotz: Ch. 17, Sec. 3-5 Moore: Ch. 16, Sec. 3-5 * Homework #9 due by 11:55 PM F Apr 8 * Quiz in second discussion section this week * Lab this week is #10, Chemical Equilibrium and Thermodynamics
Brønsted-Lowry Acids / Bases
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
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
PH and pOH in Everyday Life  Tim Wendorff
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
pH
pH and pOH  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
pH
PH and pOH in Food Color  Sofia Erazo
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
pH |
Natural Products
Weak acids in foods - pH and beyond  Sofia Erazo
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Acids / Bases |
pH |
Nutrition
The pH of Solutions of Weak Bases in Foods  Sofia Erazo
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Acids / Bases |
Nutrition |
pH
Conjugate Acid-Base Pairs and pH in Foods - From cleaning and disinfection to microbial nutrition and protein modification  Sofia Erazo
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Acids / Bases |
pH |
Nutrition
ChemPaths 104 M Apr 11  John W. Moore
Today in Chem 104: * Lecture: pH; Acid-Base Equilibria; Ionization * Reading: Kotz: Ch. 17, Sec. 6-7 Moore: Ch. 16, Sec. 7-8 * Homework #10 due by 11:55 PM F Apr 15 * Quiz in second discussion section this week * Lab this week is #6, Acid and Base Solutions
pH |
Acids / Bases |
Equilibrium
Principal Species and pH  Robert M. Hanson
Calculates concentrations of principal species in solutions using JavaScript. You can specify whether "1st-year" methods or mass-charge balance methods are used in the calculations. Solutions can be chosen from the included set or you can design your own.
Acids / Bases |
Titration / Volumetric Analysis |
pH |
Solutions / Solvents
Connected Chemistry  Mike Stieff
Connected Chemistry, a novel learning environment for teaching chemistry, is appropriate for use in both high school and undergraduate chemistry classrooms. Connected Chemistry comprises several molecular simulations designed to enable instructors to teach chemistry using the perspective of emergent phenomena. That is, it allows students to see observed macro-level chemical phenomena, like many other scientific phenomena, as resultant from the interactions of many individual agents on a micro-level. This perspective is especially appropriate to the study of chemistry where the interactions between multitudes of molecules on the atomic level give rise to the macro-level concepts that students study in the classroom. Connected Chemistry comprises molecular simulations embedded in the NetLogo modeling software (1). The collection contains several predesigned simulations of closed chemical systems to teach specific chemistry concepts. Currently, Connected Chemistry contains models for teaching Brønsted Lowry acid base theory, enzyme kinetics, radical polymerization, buffer chemistry, kinetics, chemical equilibrium, and crystallization. Instructors and students can individually tailor the predesigned simulations or generate new simulations as they are needed in the context of a particular lesson, classroom, or department.
Acids / Bases |
Gases |
Kinetics |
Nuclear / Radiochemistry |
pH |
Titration / Volumetric Analysis |
Polymerization |
Equilibrium |
Catalysis