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( Molecular)
In chemistry, a molecule is defined as a sufficiently stable electrically neutral group of at least two atoms in a definite arrangement held together by very strong chemical bonds . It can also be defined as a unit of two or more atoms held together by covalent bonds.[1][2] In organic chemistry and biochemistry, the term molecule is used less strictly and also is applied to charged organic molecules and biomolecules. Molecules are distinguished from polyatomic ions in this strict sense. This definition has evolved as knowledge of the structure of molecules has increased. Earlier definitions were less precise defining molecules as the smallest particles of pure chemical substances that still retain their composition and chemical properties.[3] This definition often breaks down since many substances in ordinary experience, such as rocks, salts, and metals, are composed of atoms or ions, but are not made of molecules. In the kinetic theory of gases the term molecule is often used for any gaseous particle regardless of their composition.[4] According to this definition noble gases would also be considered molecules despite the fact that they are composed of a single non-bonded atom. The term "molecule", from the French molécule meaning "extremely minute particle," was coined by French philosopher Rene Descartes in the 1620s. Although the existence of molecules was accepted by many chemists since the early 19th century as a result of Dalton's laws of Definite and Multiple Proportions (1803-1808) and Avogadro's law (1811), there was some resistance among positivists and physicists such as Mach, Boltzmann, Maxwell, and Gibbs, who saw molecules merely as convenient mathematical constructs. The work of Perrin on Brownian motion (1911) is considered to be the final proof of the existence of molecules.
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Molecular Subcategories
Molecular Articles
A Few Truths About The FDA by Phil Bate PhD
Almost everybody knows that the FDA (The Food and Drug Government Agency) was originally set up to protect we poor consumers from bad food and drugs. Most everybody still believes that they do that, but they're wrong!
Did you know that 80%...
Free Radicals: Destructive Scavengers and the Vital Role Antioxidants Play by Carina MacInnes
Several years ago, it was all over the news. Free radicals were damaging - we all had them, and antioxidants were the solution. But what role really do free radicals play in damaging the body, and how are we supposed to best get rid of them...
The New #1 Superfood: The Most Powerful Antioxidant Known In The World by Carina MacInnes
There has been a groundbreaking discovery in the field of health and nutrition. Though it has been featured in the media and become an underground buzz, it is still generally unknown. It is the anti- aging and health re-vitalizing power of a...
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