that slow or prevent the oxidation
of other chemicals
. Oxidation is a redox chemical reaction
that transfers electrons
from a substance to an oxidizing agent
. Oxidation reactions can involve the production of free radicals
, which can form dangerous chain reactions
. Antioxidants can terminate these chain reactions by removing radical intermediates and can inhibit other oxidation reactions by being oxidized themselves. As a result, antioxidants are often reducing agents
such as thiols
Although oxidation reactions are critical for life, they can also be damaging; hence, plants and animals maintain complex systems of multiple types of antioxidants, such as glutathione, vitamin C, and vitamin E as well as enzymes such as catalase, superoxide dismutase and various peroxidases. Low levels of antioxidant molecules or inhibition of these antioxidant enzymes causes oxidative stress and may damage or kill cells.
As oxidative stress has been implicated in the pathogenesis of many human diseases, the use of antioxidants in pharmacology is intensively studied, particularly as treatments for stroke and neurodegenerative diseases. Antioxidants are also widely used as ingredients in dietary supplements in the hope of maintaining health and preventing diseases such as cancer and coronary heart disease. In addition to these uses in medicine, antioxidants have many industrial uses, such as preservatives in food and cosmetics and preventing the degradation of rubber and gasoline.
Wikipedia:WikiProject Chemicals/Data is a collection of links and references that are useful for chemistry-related works. This includes free online chemical databases, publications, patents, computer programs, and various tools.
Science is Fun
University of Wisconsin–Madison Chemistry Professor Bassam Z. Shakhashiri, shares the fun of science.
A good place to figure out what equals what.
General Chemistry Online
Clear text and comprehensive coverage of general chemistry topics by Fred Senese, Dept. of Chemistry Frostburg State University
General Chemistry Demonstration at Purdue
Video clips (and descriptions) of lecture demonstrations.
Intota Chemistry Experts
A large online listing of real-world chemistry expert biographies provides examples of the many areas of expertise and careers in chemistry.
Chemistry Webercises Directory
A large listing of chemistry resources maintained by Steven Murov, Emeritus Chemistry Professor Modesto Junior College.
MathMol (Mathematics and Molecules) is a good starting point for those interested in the field of molecular modeling.
Educational Resources and Essential References from Wiley, the world's largest chemistry publisher
A directory of free full-text journals in chemistry, biochemistry and related subjects.
The Element Song
A goofy little song about all of the elements.