Online chemical modeling environment (OCHEM): web platform for data storage, model development and publishing of chemical information
UNC Chemistry Fundamentals
An Interactive Educational Exercise Because of special formatting tags needed to display exponents, this site is best viewed with Netscape 3.0 or higher. If needed, use the link under Useful Materials to download Netscape About the Chemistry Fundamentals Course This exercise is designed for anyone who wants an introduction or review of the fundamentals of chemistry that will be used in freshman level chemistry classes. This interactive course was used for the first time during the summer of 1997. Evaluations from last year's materials suggested that, while the mathematics and calculator sections were useful, one of the most appreciated benefits of the materials was the review of basic high school chemistry. Currently, this site is used as a resource that can be beneficial to any student that is enrolled in a freshman chemistry course. About these materials How to use these materials The basic procedure is as follows:Take the pre-test for a certain sections. About the Sidebar
Chemistry Virtual Textbook
Acid-base chemistry can be extremely confusing, particularly when dealing with weak acids and bases. This set of lessons presents an updated view of the Brønsted-Lowry theory that makes it easy to understand answers to common questions: What's the fundamental difference between a strong acid and a weak acid? Can acid A neutralize base B? Why are some salts acidic and others alkaline? This complete rewrite of the previous 1996 pdf document is now organized into seven lessons covering all aspects of the subject. Much emphasis is placed on the practical aspects of calculations, including how to deal with quadratic equations and how to judge when approximations are appropriate.
Bond Energy
If we pass a direct electric current through water containing enough ions to make it a good electrical conductor, it will break down into its constituents: hydrogen and oxygen. Both hydrogen and oxygen gas exist as diatomic molecules so the equation for this chemical reaction is The prefixes tell us that it takes 2 molecules of water to produce one molecule of oxygen and two molecules of hydrogen. Bond Energy For any particular chemical bond, say the covalent bond between hydrogen and oxygen, the amount of energy it takes to break that bond is exactly the same as the amount of energy released when the bond is formed. There are many forms of energy: electrical mechanical chemical but all forms are ultimately converted into heat. The kilocalorie is also the unit used to describe the energy content of foods. It takes a net of 118 kcal to decompose 2 moles of H2O into its elements. Let's look at the numbers. The bond energy of the H-O bond is 110 kcal. What is free energy? Cellular respiration
MSDS ARCHIVE FOR THE CNTECH LABORATORIES
MSDS (Material Safety Data Sheets) at CNTech Etchants, adhesives, plating baths, etc. Safety Information All chemicals at CNTech can be idenrified by their CAS (Chemical Abstract Service) Registry Number. This is a unique identifier that tells you, for example, that acetone and dimethyl ketone are actually the same substance. The Synchrotron Radiation Center (SRC) has a safety manual available on the Web. More information is available from the SRC Safety Officer, Bruce Neumann All chemicals at CNTech should be labeled with a hazard code chart, like the one shown below. Blue – Health Red – Flammability Yellow – Reactivity White – Special precautions For a more detailed explanation of these hazard codes, start here . Other Reference Materials A table of synonyms, structures, and uses of some common lithography molecules can be found here. Evaporation Return to the main CNTech Labs page This MSDS collection is under construction and may not include all chemicals found in the CNTEch labs. Acetic acid HBr Al
Plasmas
Plasmas exist in a wide range of settings and varieties. Most stars are made up of plasma. The Aurora Borealis is a plasma light show in our upper atmosphere caused by the bombardment from space of the solar wind - another kind of plasma. As stated in the definition, plasma is a gaseous type of state where the matter making the plasma consists of electrically neutral and charged particles. Accelerating electrons through ordinary gas can create plasma, in just the way they create lightning. If you do it in a very low pressure gas - something like the interior of an incandescent light bulb - you usually just get a kind of diffuse glow. How does a Plasma Globe Work? We apply an electric voltage to the metal electrode in the center of the plasma globe. Simultaneously, we create a changing electric field inside the globe with another, oscillating electric voltage on the electrode. Free electrons create the plasma from the regular gas atoms inside the globe.
