Oxoacids acid nomenclature

Other minor systems are also in use. Some are traditional, and some are very restricted in their application. These include acid nomenclature (inorganic, for oxoacids and derivatives), replacement nomenclature (mainly organic, to denote replacement of skeletal atoms in a parent rather than replacement of hydrogen atoms — oxa-aza replacement is one variant), functional class nomenclature (this is again principally organic and involves the use of type names such as alcohol, acid and ether) and subtractive nomenclatures (such as organic-deoxy and inorganic-debor). These will all be referred to briefly as appropriate. 

Such oxides may therefore be considered as acid anhydrides. Table above shows a selection of oxoacids with their anhydrides and illustrates the conventional nomenclature. For example, sulphurous and sulphuric acids are display the lower (+4) and higher (+6) oxidation state, respectively, and their anions are called sulphite and sulphate. 

Termination of a name of an oxoacid of a central element in an oxidation state lower than the highest. This nomenclature is not generally., J recommended phosphorous [acid]j ... 

The first level of nomenclature, beyond the assignment of totally trivial names, gives some systematic information about a substance but does not allow the inference of composition. Most of the common names of the oxoacids (e.g. sulfuric acid, perchloric acid) and of their salts are of this type. Such names may be termed semi-systematic and as long as they are used for common materials and understood by chemists, they are acceptable. However, it should be recognized that they may hinder compositional understanding by those with limited chemical training. 

The chapter on Oxoacids and Derived Anions (Red Book I, Chapter 1-9) has also been extensively modified. Now called Inorganic Acids and Derivatives (Chapter IR-8), it includes the slightly revised concept of hydrogen names in Section IR-8.4 (and some traditional ous and ic names have been reinstated for consistency and because they are required for organic nomenclature purposes, i.e. in the new Blue Book). 

Examples of oxoacids include hypochlorous acid (HOCl), perchloric acid (HCIO4), nitric acid (HNO3), sulfuric acid (H2SO4) and phosphoric acid (H3PO4). Many well-recognized common names exist for oxoacids, and the lUPAC has recommended that such names be retained. In this book, we follow this recommendation, although in Box 6.2 we introduce systematic nomenclature. 

Inorganic chemists also use a further termination to indicate the name of a cation. This is the ending -ate, and it is used as a modification of the name of an oxoacid. Thus sulfuric acid, H2SO4, gives rise to sulfate, S04, phosphoric acid to phosphate, P04, and nitric acid to nitrate, NO3. The partially deprotonated anions such as HS04 and H2P04 are rather more comphcated to deal with, and are discussed in Nomenclature of Inorganic Chemistry, often referred to as the Red Book. 

Our network of ideas can be applied to oxides, which divide into metal ionic and nonmetal covalent types. Ionic oxides are basic anhydrides that produce metal hydroxides and hydroxide ions in aqueous solution. Nonmetal oxides are acidic anhydrides that produce oxoacids and hydronium ions in solution. These correlations have become the sixth component of our network of ideas. The relative strengths of oxoacids and hydroacids can be rationalized by using other parts of the network. A systematic approach to the nomenclature of the oxoacids is based on the five representative -ic acids. 

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