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reza-1369
23rd September 2012, 08:19 PM
http://upload.wikimedia.org/wikipedia/commons/thumb/8/8d/Al-RaziInGerardusCremonensis1250.JPG/220px-Al-RaziInGerardusCremonensis1250.JPG (http://en.wikipedia.org/wiki/File:Al-RaziInGerardusCremonensis1250.JPG)
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Muhammad ibn Zakariya ar-Razi (http://en.wikipedia.org/wiki/Muhammad_ibn_Zakariya_ar-Razi) (Rhazes),the Persian chemist and most famous alchemist,the inventor of alcohol (http://en.wikipedia.org/wiki/Alcohol), isolated many chemical substances (http://en.wikipedia.org/wiki/Chemical_substance), produced many medications (http://en.wikipedia.org/wiki/Medication), and described many laboratory apparatus.




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Antoine Lavoisier (1743–94) is considered the "Father of Modern Chemistry (http://en.wikipedia.org/wiki/People_known_as_the_father_or_mother_of_something)".





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A chemist is a scientist (http://en.wikipedia.org/wiki/Scientist) trained in the study of chemistry (http://en.wikipedia.org/wiki/Chemistry). Chemists study the composition of matter and its properties such as density and acidity. Chemists carefully describe the properties they study in terms of quantities, with detail on the level of molecules (http://en.wikipedia.org/wiki/Molecule) and their component atoms (http://en.wikipedia.org/wiki/Atom). Chemists carefully measure substance proportions, reaction (http://en.wikipedia.org/wiki/Chemical_reaction) rates, and other chemical properties (http://en.wikipedia.org/wiki/Chemical_properties).
Chemists use this knowledge to learn the composition, and properties of unfamiliar substances, as well as to reproduce and synthesize large quantities of useful naturally occurring substances and create new artificial substances and useful processes. Chemists may specialize in any number of subdisciplines of chemistry (http://en.wikipedia.org/wiki/Chemistry#Subdisciplines). Materials scientists (http://en.wikipedia.org/wiki/Materials_science) and metallurgists share much of the same education and skills with chemists. The work of chemists is often related to the work of chemical engineers (http://en.wikipedia.org/wiki/Chemical_engineer), which are primarily concerned with the proper design, construction and evaluation of the most cost-effective large-scale chemical plants (http://en.wikipedia.org/wiki/Chemical_plant) and work closely with industrial chemists on the development of new processes and methods for the commercial-scale manufacture of chemicals and related products
History


Main article: History of chemistry (http://en.wikipedia.org/wiki/History_of_chemistry)
The roots of chemistry can be traced to the phenomenon of burning (http://en.wikipedia.org/wiki/Combustion). Fire (http://en.wikipedia.org/wiki/Fire) was a mystical force that transformed one substance into another and thus was of primary interest to mankind. It was fire that led to the discovery (http://en.wikipedia.org/wiki/Discovery_%28observation%29) of iron (http://en.wikipedia.org/wiki/Iron) and glass (http://en.wikipedia.org/wiki/Glass). After gold (http://en.wikipedia.org/wiki/Gold) was discovered and became a precious metal, many people were interested to find a method that could convert other substances into gold. This led to the protoscience (http://en.wikipedia.org/wiki/Protoscience) called Alchemy (http://en.wikipedia.org/wiki/Alchemy). The word chemist is derived from the New Latin (http://en.wikipedia.org/wiki/New_Latin) noun chimista, an abbreviation of alchimista (alchemist (http://en.wikipedia.org/wiki/Alchemy)). Alchemists discovered many chemical processes (http://en.wikipedia.org/wiki/Chemical_process) that led to the development of modern chemistry. Chemistry as we know it today, was invented by Antoine Lavoisier (http://en.wikipedia.org/wiki/Antoine_Lavoisier) with his law of Conservation of mass (http://en.wikipedia.org/wiki/Conservation_of_mass) in 1783. The discoveries of the chemical elements (http://en.wikipedia.org/wiki/Discoveries_of_the_chemical_elements) has a long history culminating in the creation of the periodic table (http://en.wikipedia.org/wiki/Periodic_table) by Dmitri Mendeleev (http://en.wikipedia.org/wiki/Dmitri_Mendeleev). The Nobel Prize in Chemistry (http://en.wikipedia.org/wiki/Nobel_Prize_in_Chemistry) created in 1901 gives an excellent overview of chemical discovery since the start of the 20th century.
Education


Jobs for chemists usually require at least a bachelor's degree (http://en.wikipedia.org/wiki/Bachelor%27s_degree), but many positions, especially those in research, require a Ph.D (http://en.wikipedia.org/wiki/Ph.D). Most undergraduate programs emphasize mathematics (http://en.wikipedia.org/wiki/Mathematics) and physics (http://en.wikipedia.org/wiki/Physics) as well as chemistry, partly because chemistry is also known as "the central science (http://en.wikipedia.org/wiki/The_central_science)", thus chemists ought to have a well-rounded knowledge about science. At the Master's (http://en.wikipedia.org/wiki/Master%27s_degree) level and higher, students tend to specialize in a particular field. Fields of specialization include biochemistry (http://en.wikipedia.org/wiki/Biochemistry), nuclear chemistry (http://en.wikipedia.org/wiki/Nuclear_chemistry), organic chemistry (http://en.wikipedia.org/wiki/Organic_chemistry), inorganic chemistry (http://en.wikipedia.org/wiki/Inorganic_chemistry), polymer chemistry (http://en.wikipedia.org/wiki/Polymer_chemistry), analytical chemistry (http://en.wikipedia.org/wiki/Analytical_chemistry), theoretical chemistry (http://en.wikipedia.org/wiki/Theoretical_chemistry), quantum chemistry (http://en.wikipedia.org/wiki/Quantum_chemistry), environmental chemistry (http://en.wikipedia.org/wiki/Environmental_chemistry), and physical chemistry (http://en.wikipedia.org/wiki/Physical_chemistry). Postdoctoral (http://en.wikipedia.org/wiki/Postdoctoral) experience may be required for certain positions.
Workers whose work involves chemistry, but not at a complexity requiring an education with a chemistry degree, are commonly referred to as chemical technicians (http://en.wikipedia.org/wiki/Chemical_technician). Such technicians commonly do such work as simpler, repetitive analyses for quality control (http://en.wikipedia.org/wiki/Quality_control) or in clinical laboratories (http://en.wikipedia.org/wiki/Clinical_laboratory).
Employment


The three major employers of chemists are academic institutions, industry, especially the chemical industry (http://en.wikipedia.org/wiki/Chemical_industry) and the pharmaceutical industry (http://en.wikipedia.org/wiki/Pharmaceutical_industry), and government laboratories.
Chemistry typically is divided into several major sub-disciplines. There are also several main cross-disciplinary and more specialized fields of chemistry. There is a great deal of overlap between different branches of chemistry, as well as with other scientific fields such as biology, medicine, physics, radiology (http://en.wikipedia.org/wiki/Radiology), and several engineering disciplines.
Analytical chemistry (http://en.wikipedia.org/wiki/Analytical_chemistry) is the analysis of material samples to gain an understanding of their chemical composition (http://en.wikipedia.org/wiki/Chemical_composition) and structure (http://en.wikipedia.org/wiki/Structure). Analytical chemistry incorporates standardized experimental methods in chemistry. These methods may be used in all subdisciplines of chemistry, excluding purely theoretical chemistry.
Biochemistry (http://en.wikipedia.org/wiki/Biochemistry) is the study of the chemicals (http://en.wikipedia.org/wiki/Chemical_compound), chemical reactions (http://en.wikipedia.org/wiki/Chemical_reaction) and chemical interactions (http://en.wikipedia.org/wiki/Chemical_interaction) that take place in living organisms (http://en.wikipedia.org/wiki/Organism). Biochemistry and organic chemistry are closely related, for example, in medicinal chemistry (http://en.wikipedia.org/wiki/Medicinal_chemistry).


http://upload.wikimedia.org/wikipedia/commons/e/e9/Laura_Miller_at_ANL.jpg (http://en.wikipedia.org/wiki/File:Laura_Miller_at_ANL.jpg)
A chemist prepares a new fuel cell (http://en.wikipedia.org/wiki/Fuel_cell) for testing.



http://upload.wikimedia.org/wikipedia/commons/d/dd/Julie_Perkins_at_LLNL.jpg (http://en.wikipedia.org/wiki/File:Julie_Perkins_at_LLNL.jpg)
A chemist pours from a round-bottom flask (http://en.wikipedia.org/wiki/Round-bottom_flask).




Inorganic chemistry (http://en.wikipedia.org/wiki/Inorganic_chemistry) is the study of the properties and reactions of inorganic compounds. The distinction between organic and inorganic disciplines is not absolute and there is much overlap, most importantly in the sub-discipline of organometallic chemistry (http://en.wikipedia.org/wiki/Organometallic_chemistry). Inorganic chemistry (http://en.wikipedia.org/wiki/Inorganic_chemistry) is also the study of atomic and molecular structure and bonding.
Medicinal chemistry (http://en.wikipedia.org/wiki/Medicinal_chemistry) is the science involved with designing, synthesizing and developing pharmaceutical drugs. Medicinal chemistry involves the identification, synthesis and development of new chemical entities suitable for therapeutic use. It also includes the study of existing drugs, their biological properties, and their quantitative structure-activity relationships.
Organic chemistry (http://en.wikipedia.org/wiki/Organic_chemistry) is the study of the structure, properties, composition, mechanisms, and chemical reaction of organic compounds.
Physical chemistry (http://en.wikipedia.org/wiki/Physical_chemistry) is the study of the physical fundamental basis of chemical systems and processes. In particular, the energetics and dynamics of such systems and processes are of interest to physical chemists. Important areas of study include chemical thermodynamics, chemical kinetics, electrochemistry, quantum chemistry, statistical mechanics, and spectroscopy. Physical chemistry has large overlap with theoretical chemistry and molecular physics. Physical chemistry involves the use of calculus in deriving equations.
Theoretical chemistry (http://en.wikipedia.org/wiki/Theoretical_chemistry) is the study of chemistry via theoretical reasoning (usually within mathematics (http://en.wikipedia.org/wiki/Mathematics) or physics (http://en.wikipedia.org/wiki/Physics)). In particular the application of quantum mechanics (http://en.wikipedia.org/wiki/Quantum_mechanics) to chemistry is called quantum chemistry (http://en.wikipedia.org/wiki/Quantum_chemistry). Since the end of the Second World War, the development of computers has allowed a systematic development of computational chemistry (http://en.wikipedia.org/wiki/Computational_chemistry), which is the art of developing and applying computer programs (http://en.wikipedia.org/wiki/Computer_program) for solving chemical problems. Theoretical chemistry has large overlap with condensed matter physics (http://en.wikipedia.org/wiki/Condensed_matter_physics) and molecular physics (http://en.wikipedia.org/wiki/Molecular_physics).See Reductionism (http://en.wikipedia.org/wiki/Reductionism).
All the above major areas of chemistry employ chemists. Other fields where chemical degrees are useful include Astrochemistry (http://en.wikipedia.org/wiki/Astrochemistry) (and Cosmochemistry (http://en.wikipedia.org/wiki/Cosmochemistry)), Atmospheric chemistry (http://en.wikipedia.org/wiki/Atmospheric_chemistry), Chemical Engineering (http://en.wikipedia.org/wiki/Chemical_Engineering), Chemo-informatics (http://en.wikipedia.org/wiki/Chemo-informatics), Electrochemistry (http://en.wikipedia.org/wiki/Electrochemistry), Environmental science (http://en.wikipedia.org/wiki/Environmental_science), Forensic science (http://en.wikipedia.org/wiki/Forensic_science), Geochemistry (http://en.wikipedia.org/wiki/Geochemistry), Green chemistry (http://en.wikipedia.org/wiki/Green_chemistry), History of chemistry (http://en.wikipedia.org/wiki/History_of_chemistry), Materials science (http://en.wikipedia.org/wiki/Materials_science), Medical science (http://en.wikipedia.org/wiki/Medical_science), Molecular Biology (http://en.wikipedia.org/wiki/Molecular_Biology), Molecular genetics (http://en.wikipedia.org/wiki/Molecular_genetics), Nanotechnology (http://en.wikipedia.org/wiki/Nanotechnology), Nuclear chemistry (http://en.wikipedia.org/wiki/Nuclear_chemistry), Oenology (http://en.wikipedia.org/wiki/Oenology), Organometallic chemistry (http://en.wikipedia.org/wiki/Organometallic_chemistry), Petrochemistry (http://en.wikipedia.org/wiki/Petrochemistry), Pharmacology (http://en.wikipedia.org/wiki/Pharmacology), Photochemistry (http://en.wikipedia.org/wiki/Photochemistry), Phytochemistry (http://en.wikipedia.org/wiki/Phytochemistry), Polymer chemistry (http://en.wikipedia.org/wiki/Polymer_chemistry), Supramolecular chemistry (http://en.wikipedia.org/wiki/Supramolecular_chemistry) and Surface chemistry (http://en.wikipedia.org/wiki/Surface_chemistry).
It has been suggested that chemists going into employment in scientific research should honor a Hippocratic Oath for Scientists (http://en.wikipedia.org/wiki/Hippocratic_Oath_for_Scientists) which is required as a Professional Chemist (http://en.wikipedia.org/wiki/Professional_Chemist)

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