Oxidation is the most important high temperature reaction. Metal or alloy oxidation takes place when it is heated in a strongly oxidising environment, such as air or oxygen. The term oxidation refers to any chemical change in which there is an increase in oxidation number while the term reduction refers to any change resulting in decrease in oxidation number. Thus oxidation proceeds with loss of electrons while reduction is accompanied by gain of electrons.
An oxidation begins with adsorption of oxygen molecules from the atmosphere, nucleation of oxides, formation of a thin oxide layer followed by its growth to a thicker layer. In the simplest form, an oxidation reaction is represented by the interaction of metal with oxygen to form an oxide. How to find oxidation number?, Oxidation number of an element is the change which its atoms have or appear to have in its ions when present in the combined state . It is also known as oxidation state. The oxidation number of an element in the free or uncombined state is zero. Fluorine , the most electronegative element, has an oxidation number of -1 always in all its compounds.
Oxidation Reaction Organic Chemistry
Oxidation reaction is the opposite of reduction. Oxidative reactions are an important process in Nature and constitute one of the most fundamental chemical transformations in organic synthesis. What is oxidation? Oxidation involves the removal of electrons and or hydrogen atoms and the supply of oxygen to another molecule. Oxidation reactions are very important reactions in organic chemistry and many of these reactions are used in synthetic organic chemistry to transform the functionalities of molecules into other functionalities.
Oxidation reactions are also important in the combustion of some compounds that release large amounts of energy in the form of heat. One of the easiest oxidizing agents to recognize is oxygen. We are all familiar with rust, which is a form of oxidation in which oxygen oxidizes metals. There are other oxidising agents and most that are used in organic chemistry typically contain a number of oxygen atoms. Some of the most commonly used oxidizing agents are oxygen, potassium permanganate and ozone.
What is the Oxidation Number?
Oxidation numbers provide a way of following shifts in electron density. Oxidation number of an element is the change which its atoms have or appear to have in its ions when present in the combined state. It is also known as oxidation state. Oxidation number of all neutral atoms, molecules, compounds, complexes, and polymeric forms is zero. For example, oxygen in water has an oxidation number of -2, since the pair of electrons in the covalent bond between oxygen and hydrogen to the more electronegative oxygen atom. The two hydrogen atoms will then each have oxidation number of +1.
Oxidation reactions are the main providers of energy for ATP synthesis. Whilst oxidation usually involves incorporation of one or more oxygen atoms, in its simplest form it can be thought of as a loss of electrons. Thus an oxidation number can be defined as the real or hypothetical charge an atom carries in its pure or compound state.