Saturday, 2 May 2015

Chemical Reaction

Chemical reaction

A chemical reaction is a transformation of the material that occurs without measurable changes of mass, in which one or more chemical species (known as "reagents") modify their structure and original composition to generate other chemical species (called "products"). This occurs through the formation or breaking of the so-called "chemical bonds intramolecular", that is, through a rearrangement of the forces of electrostatic nature which intervene between the individual atoms of which are constituted the molecular entities that are involved in the reaction. These electrostatic forces are in turn related to the effect of the outer electrons of each atom.

Some processes in which chemical reactions are involved:

the corrosion of iron in rust (which is composed of iron oxides);
the combustion of methane or other fuels (methane with oxygen is transformed into carbon dioxide and water vapor);

digestion (food are decomposed by gastric juices into chemicals absorbed by the body);
the solubilization and the formation of mixtures in liquid and solid states generates complexation reactions and dissociation.

A reaction can not take place, or is slowed to a stop or even to regress if not satisfied a number of conditions, such as the presence of the reagents to an appropriate extent and conditions of temperature, pressure and light suitable for the specific reaction.