Naming systems acids

The nomenclature (qv) of polyamides is fraught with a variety of systematic, semisystematic, and common naming systems used variously by different sources. In North America the common practice is to call type AB or type AABB polyamides nylon-x or nylon-respectively, where x refers to the number of carbon atoms between the amide nitrogens. For type AABB polyamides, the number of carbon atoms in the diamine is indicated first, followed by the number of carbon atoms in the diacid. For example, the polyamide formed from 6-aminohexanoic acid [60-32-2] is named nylon-6 [25038-54-4], that formed from 1,6-hexanediamine [124-09-4] or hexamethylenediamine and dodecanedioic acid [693-23-2] is called nylon-6,12 [24936-74-1]. In Europe, the common practice is to use the designation "polyamide," often abbreviated PA, instead of "nylon" in the name. Thus, the two examples above become PA-6 and PA-6,12, respectively. PA is the International Union of Pure and AppHed Chemistry (lUPAC) accepted abbreviation for polyamides. 

The name hydroxamic acid was first used by Losseii in 1869, in the case of oxalohj droxamic acid, obtained from diethyl oxalate and hydroxylamine. Where this grouping forms part of the main cyclic system, however, the compound is named as a derivative of this system. In this review, 2 and 3 would be named as 1-hydroxy-2-pyrrolidone and l-hydroxy-2-pyridone, respectively. 

As further examples, compounds 10 and 11 are both keto acids and mus be named as acids, but the parent name in 10 is that of a ring system (cyclo hexanecarboxylic acid) and the parent name in 11 is that of an open chair (propanoic acid). The full names are frrt/ s-2-(3-oxopropyl)cyclohexane carboxylic acid (10) and 3-(2-oxocyclohexyl)propanoic acid (11). 

For the tetraric acids, the trivial name tartaric acid remains in use, with the stereochemistry given using the R,S system. Esters are referred to as tartrates (the second a is elided). 

Presumably, at some point in history a batch of unleavened bread dough became contaminated with wild yeast and the first leavened bread was made. The only way in which such a system can be kept going is to keep back a portion of the old dough and add more flour and water to keep the fermentation going. In such a system various side-reactions occur and fatty acids start to be produced, hence the name. The acids give the dough some protection from contamination with undesirable moulds, which would be an advantage in a primitive society. 

Many hydrogen compounds are acids. Acids require a different system of nomenclature than other compounds. There are two types of acids binary acids and ternary acids. All acids include the word acid in their name. Binary acids contain only two elements one of which is hydrogen and the other a nonmetal. When naming binary acids, the prefix hydro- appears before the root name of the nonmetal, and there will be an -ic suffix. As an acid, H2S would be hydrosulfuric acid. We used H2S to illustrate the fact that there can be two possible names, hydrogen sulfide or hydrosulfuric acid. If your instructor does not specify which name to use, either is correct. Technically, the name hydrosulfuric acid only applies to aqueous solutions of H2S, H2S(aq). 

The chemical compounds known as acids have their own special naming system, but writing the names and formulas of acids really isn t that big of a deal. As long as you pay attention to the details, you won t have any problem naming acidic compounds. You more than likely already know the names of several very common acids, though perhaps you don t know their formulas. Table 6-3 lists several of the most common acids and their formulas. (Flip to Chapter 16 for full details on acids.)... 

The plasmodia of the wild type of Physarum polycephalum are bright yellow and produce an orange-red pigment that is also present in a white mutant [120]. This compound, named physarorubinic acid (64), binds calcium and other metals very well and this made acquisition of the H-NMR spectrum difficult (line broadening) unless the sample was washed with aq. EDTA solution. The structure contains a decapentaene system and signals at 5 102.4 (C-3), 172.6 (C-7), 174.5 (C-2) and 194.0 (C-4) are characteristic of C-3 acylated tetramic acid unit. 

Two systems are used for naming carboxylic acids the common system and the IUPAC system. 

Aldehydes, acids, and esters have roots for one and two carbons that are usually form- and acet-, rather than meth- and eth-, because these prefixes had been used so long they were grandfathered into the naming system (formaldehyde and acetic acid, rather than methanal and ethanoic acid). Departures from IUPAC nomenclature often occur for very common substances and, fortunately, they rarely can be misunderstood (ethyl alcohol instead of ethanol). 

Nomenclature, the naming system for chemical compounds, is summarized in Figures 11.4 and 11.5. Nomenclature for acids is not included in the chart. 

In recent years a considerable amount of fascinating new chemistry has been carried out in several highly acidic systems. This is exemplified by the preparation of stable solutions of aliphatic carbonium ions (Olah et al., 1965), the formation of a variety of new inorganic cations, e.g., the If and Sef+ cations (Gillespie, 1968), and the protonation of some unusual very weak bases such as carbonic acid to give C(OH)J (Olah and White, 1968). There has, however, been rather little fundamental information available on these systems and in particular on one of their most important and fundamental properties, namely their acidity. In this review we discuss the properties of systems which have acidities comparable to, or greater than, that of 100% H2S04. 

Synonyms and trade names picronitric acid, 2,4,6-trinitrophenol, trinitrophenol Use and exposure Picric acid is a white to yellowish crystalline substance and highly flammable. It is used in the manufacture of fireworks, matches, electric batteries, colored glass, explosives, and disinfectants. Pharmaceutical, textile, and leather industries also make use of picric acid. Bouin s picro-formol is used as a preservative solution for biological specimens in laboratories. Toxicity and health effects Picric acid causes different adverse effects on the skins of animals and humans, like allergies, dermatitis, irritation, and sensitization. Absorption of picric acid by the system causes headache, fever, nausea, diarrhea, and coma. In high concentrations, picric acid is known to... 

The following three systems of nomenclature are in use for naming fatty acids. 

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