Search results
Results from the WOW.Com Content Network
The phosphotungstate anion, an example of a polyoxometalate. In chemistry, a polyoxometalate (abbreviated POM) is a polyatomic ion, usually an anion, that consists of three or more transition metal oxyanions linked together by shared oxygen atoms to form closed 3-dimensional frameworks.
The cation is always named first. Ions can be metals, non-metals or polyatomic ions. Therefore, the name of the metal or positive polyatomic ion is followed by the name of the non-metal or negative polyatomic ion. The positive ion retains its element name whereas for a single non-metal anion the ending is changed to -ide.
Polyatomic ions often are useful in the context of acid–base chemistry and in the formation of salts. Often, a polyatomic ion can be considered as the conjugate acid or base of a neutral molecule. For example, the conjugate base of sulfuric acid (H 2 SO 4) is the polyatomic hydrogen sulfate anion (HSO − 4).
Ions consisting of only a single atom are termed atomic or monatomic ions, while two or more atoms form molecular ions or polyatomic ions. In the case of physical ionization in a fluid (gas or liquid), "ion pairs" are created by spontaneous molecule collisions, where each generated pair consists of a free electron and a positive ion. [5]
The explanation for the behavior is complicated, having to do with various cluster-forming tendencies of HF, water, and fluoride ion, as well as thermodynamic issues. [note 3] At great concentrations, a property called homoconjugation is revealed. HF begins to accept fluoride ions, forming the polyatomic ions (such as bifluoride, HF −
Functional groups can also be charged, e.g. in carboxylate salts (−COO −), which turns the molecule into a polyatomic ion or a complex ion. Functional groups binding to a central atom in a coordination complex are called ligands. Complexation and solvation are also caused by specific interactions of functional groups.
The bicarbonate ion (hydrogencarbonate ion) is an anion with the empirical formula HCO − 3 and a molecular mass of 61.01 daltons; it consists of one central carbon atom surrounded by three oxygen atoms in a trigonal planar arrangement, with a hydrogen atom attached to one of the oxygens. It is isoelectronic with nitric acid HNO 3.
In chemistry, peroxides are a group of compounds with the structure R−O−O−R, where the R's represent a radical (a portion of a complete molecule; not necessarily a free radical [1]) and O's are single oxygen atoms. [2] [3] Oxygen atoms are joined to each other and to adjacent elements through single covalent bonds, denoted by dashes or lines.