A chemical species is a
chemical substance
A chemical substance is a form of matter having constant chemical composition and characteristic properties. Some references add that chemical substance cannot be separated into its constituent elements by physical separation methods, i.e., w ...
or ensemble composed of chemically identical
molecular entities that can explore the same set of molecular energy levels on a characteristic or delineated time scale. These energy levels determine the way the chemical species will interact with others (engaging in
chemical bond
A chemical bond is a lasting attraction between atoms or ions that enables the formation of molecules and crystals. The bond may result from the electrostatic force between oppositely charged ions as in ionic bonds, or through the sharing of ...
s, etc.). The species can be an atom, molecule, ion, or radical, and it has a specific
chemical name and
chemical formula. The term is also applied to a set of chemically identical atomic or molecular structural units in a solid array.
Chemical Species , Facts, Summary & Definition , Chemistry Revision
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In supramolecular chemistry
Supramolecular chemistry refers to the branch of chemistry concerning chemical systems composed of a discrete number of molecules. The strength of the forces responsible for spatial organization of the system range from weak intermolecular forces ...
, chemical species are those supramolecular structures whose interactions and associations are brought about via intermolecular bonding and debonding actions, and function to form the basis of this branch of chemistry.
For instance:
* The chemical species argon is an atomic species of formula Ar;
* dioxygen
There are several known allotropes of oxygen. The most familiar is molecular oxygen (O2), present at significant levels in Earth's atmosphere and also known as dioxygen or triplet oxygen. Another is the highly reactive ozone (O3). Others are:
* ...
and ozone
Ozone (), or trioxygen, is an inorganic molecule with the chemical formula . It is a pale blue gas with a distinctively pungent smell. It is an allotrope of oxygen that is much less stable than the diatomic allotrope , breaking down in the lower ...
are different molecular species, of respective formulas O and O;
* chloride is an ionic species; its formula is Cl;
* nitrate is a molecular and ionic species; its formula is NO;
* methyl is a molecular and radical species; its formula is CH;
* sodium chloride
* DNA is ''not'' a species: the name is generically applied to many molecules of different formulas (each DNA molecule is unique).
See also
* List of particles
References
Chemical substances
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