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The Chemistry Portal

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P:CHEM
Colourful solutions in test-tubes.
Welcome to the chemistry portal. Chemistry, from Greek language χυμεία meaning "study of liquids", is a branch of science. Modern chemistry focuses on the study of elements of the world and the bonds between elements. Chemistry also deals with composition, structure, and properties of substances and the transformations that they undergo. In the study of matter, chemistry also investigates its interactions with energy and itself. Because of the diversity of matter, which is mostly in the form of compounds, chemists often study how atoms of different chemical elements interact to form molecules, and how molecules interact with each other.


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Featured article - Selected picture - News - Selected biography - History and Philosophy - Techniques - Equipment - Chemistry in society - Chemistry in industry - Periodic Table - Resources - WikiProjects - Things you can do - Collaboration of the month - Related portals - Associated Wikimedia


  

Featured article

A ribbon diagram of Dihydrofolate reductase
Enzyme kinetics is the study of the rates of chemical reactions that are catalysed by enzymes. The study of an enzyme's kinetics provides insights into the catalytic mechanism of this enzyme, its role in metabolism, how its activity is controlled in the cell and how drugs and poisons can inhibit its activity.

Enzymes are molecules that manipulate other molecules — the enzymes' substrates. These target molecules bind to an enzyme's active site and are transformed into products through a series of steps known as the enzymatic mechanism. Some enzymes bind multiple substrates and/or release multiple products, such as a protease cleaving one protein substrate into two polypeptide products. Others join substrates together, such as DNA polymerase linking a nucleotide to DNA. Although these mechanisms are often a complex series of steps, there is typically one rate-determining step that determines the overall kinetics. This rate-determining step may be a chemical reaction or a conformational change of the enzyme or substrates, such as those involved in the release of product(s) from the enzyme.

  

Selected picture

Gallium crystals
Credit: Greatpatton

Gallium is a chemical element in the periodic table that has the symbol Ga and atomic number 31. A rare, soft silvery metallic poor metal, gallium is a brittle solid at low temperatures but liquefies slightly above room temperature and indeed will melt in the hand. It occurs in trace amounts in bauxite and zinc ores. An important application is in the compound gallium arsenide, used as a semiconductor, most notably in light-emitting diodes (LEDs).

  

Categories

  

History and Philosophy of Chemistry

Antoine Lavoisier

Many chemists have an interest in the history of chemistry. Those with philosophical interests will be interested that the philosophy of chemistry has quite recently developed along a path somewhat different from the general philosophy of science.

Other articles that might interest you are:

There is a Wikipedia Project on the History of Science and portals for the scientific method and philosophy of science.

  

Chemistry Resources

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.

megaConverter The Web's best 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 MathMol (Mathematics and Molecules) is a good starting point for those interested in the field of molecular modeling.

Chemistry Educational Resources and Essential References from Wiley, the world's largest chemistry publisher

ABC Chemistry A directory of free full-text journals in chemistry, biochemistry and related subjects.

  

In the news

Rohm and Haas Headquarters in 2007.
Rohm and Haas Headquarters in 2007.
  • 7-10 US chemical giant Dow Chemical has announced that it is to buy Philadelphia-based rival Rohm and Haas. Dow is paying $78 per share, a 74 percent premium, which makes the agreement worth around $15.3 billion. The change will expand Dow's presence in the specialty chemical market. Dow plans to set up an advanced materials business unit at the Rohm and Haas headquarters in Philadelphia, and this unit will retain the Rohm and Haas name. Read more...
  • 2-15 Chemists modeling the structure of strongly acidic solutions have found that hydronium ions can associate into unusual ion pairs. Gregory A. Voth and Sergei Izvekov of the University of Utah, in collaboration with Feng Wang of Boston University, were examining the structure of aqueous hydrochloric acid at concentrations of 0.43-0.85 M, and they found that the ions unexpectedly associate into pairs. See doi:10.1021/ja078106i Read more...
  

Selected biography

Harold Urey
Harold Urey (1893-1981) was an American physical chemist, who won the 1934 Nobel Prize in Chemistry for his work on isotopes, specifically the discovery of deuterium, a hydrogen isotope, and the production of heavy water. He also performed pioneering research in cosmochemistry, which studies the origin and development of elements and their isotopes, primarily within the solar system. Urey, along with his student Stanley Miller, may be best remembered for the renowned Miller-Urey experiment, which shows that a mixture of ammonia, methane and hydrogen, when exposed to ultraviolet radiation and water, can interact to form amino acids, the "building blocks" of terrestrial life. This experiment followed on from Urey's work on the oxygen isotope 18O, and is considered to be pioneering work in the field of paleoclimatology, as it attempts to explain the composition of the early Earth's atmosphere.
  

Techniques used by chemists

  

Equipment used by chemists

  

Chemistry in society

  

Chemistry in industry

  

WikiProjects

  

Periodic Table

  

Things you can do

Here are some things you can do:

  

Collaboration of the Month

The current Chemistry Collaboration of the Month is Catalysis.
Every month a different chemistry-related topic, stub or non-existent article is picked. Please improve the article any way you can.
  

Related portals

  

Associated Wikimedia
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