Friday, October 29, 2010

Molecule

Molecule is the smallest particle of an element or compound. It can exist independently and can take part in a chemical reaction. A concept introduced by Italian physicist Amedeo Avogadro (1776-1856)  that Water is not just a collection of "water atoms": clearly, there is some sort of intermediary structure in which atoms are combined. This is the molec...

Atom

In 1803, English chemist John Dalton (1766-1844) defined that substructure by introducing the idea that the material world is composed of tiny particles called atoms. Atom is the smallest particle of an element, having all the properties of that element.It can take part in a chemical reaction. Symbol of an atom is same as the symbol of an element.Thus H stands for one atom of Hydrogen, N stands for one atom of Nitro...

Element and its Properties

It is the simplest form of Matter, which cannot be further simplified by any physical or chemical mean, is known as Element. There are about 113 elements, out of which 92 are natural, rest are man made. Examples of Natural Elements are H, O, N, Fe, Na, etc. There are two properties of Elements (1) Physical Properties: These are the properties which are associated with physical changes in a substance. Examples are color, shape, temperature, etc (2) Chemical Properties: These are the properties which are associated with the fundamental composition of a substance. Examples are Bonding Nature, Catalytic...

Matter and its states

Any thing which occupy the space and has a volume is called Matter. There are three States of Matter (1) Solid: It is the state in which matter maintains a fixed volume and shape. (2) Liquid: It is the state in which matter maintains a fixed volume but adapts to the shape of its container (3) Gas: It is the state in which matter expands to occupy whatever volume is availa...

Chemistry definations

Chemistry is the science of matter In retrospect, the definition of chemistry seems to invariably change per decade, as new discoveries and theories add to the functionality of the science. Shown below are some of the standard definitions used by various noted chemists:Alchemy (330) – the study of the composition of waters, movement, growth, embodying, disembodying, drawing the spirits from bodies and bonding the spirits within bodies (Zosimos). Chymistry (1661) – the subject of the material principles of mixt bodies (Boyle). Chymistry (1663) – a scientific art, by which one learns...

History of chemistry

The word chemistry comes from the earlier study of alchemy, which is a set of practices that encompasses elements of chemistry, metallurgy, philosophy, astrology, astronomy, mysticism and medicine. Alchemy in turn is derived from the Arabic word "كيمياء" meaning "value", it is commonly thought of as the quest to turn lead or another common starting material into gold. This linguistic relation between the pursuit of value and alchemy is thought to have Egyptian origins. Many believe that the Arabic word "alchemy" is derived from the word Chemi or Kimi,...

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