Penta prefix

Stoichiometric Proportions. The stoichiometric proportions of the constituents in a formula may be denoted by Greek numerical prefixes mono-, di-, tri-, tetra-, penta-, hexa-, hepta-, octa-, nona- (Latin), deca-, undeca- (Latin), dodeca-,. . . , icosa- (20), henicosa- (21),. . . , tri-conta-(30), tetraconta-(40),. . . , hecta-(100), and so on, preceding without a hyphen the names of the elements to which they refer. The prefix mono can usually be omitted occasionally hemi-(1/2) and sesqui- (%) are used. No elisions are made when using numerical prefixes except in the case of icosa- when the letter i is elided in docosa- and tricosa-. Beyond 10, prefixes may be replaced by Arabic numerals. 

When the prefixes tetra, penta, hexa,. .. are followed by the letter o, the a is often dropped. For example, N2Os is often referred to as dinitrogen pentoxide. 

The number of ligands of a particular type is ordinarily indicated by the Greek prefixes di, tri, tetra, penta, hexaz... 

The prefixes di-, tri-, tetra-, penta-, bexa-, and so on, indicate how many of each substituent are in the molecule. Numbers set off by hyphens specify to which carbon atoms the groups are attached. 

The all-trans-all-isotactic and all-trans-all-syndiotactic structures for the 1,4-polymerization of 1,3-pentadiene are shown in Fig. 8-6. In naming polymers with both types of stereoisomerism, that due to cis-trans isomerism is named first unless it is indicated after the prefix poly. Thus, the all-trans-all-isotactic polymer is named as transisotactic l,4-poly(l,3-penta-diene) or isotactic poly( -3-methylbut-l-ene-l,4-diyl). 

However, higher members of the series are named systematically by combining the ending -ane, characteristic of the first four members and implying complete saturation, with a multiplicative prefix of the series penta-, hexa-, etc. of Table 4.2, which indicates the number of carbon atoms constituting the chain. The letter a , which ends the name of the multiplicative prefix, is elided. 

Continuing in the alkane series (also called the paraffin series because the first solid hydrocarbon in the series is paraffin, or candle wax), the next compound is pentane. This name is derived from the Greek word penta, for five. As its name implies, it has five carbon atoms, and its molecular formula is C,H12. From pentane on, the Greek prefix for the numbers five, six, seven, eight, nine, ten, and so on are used to name the alkanes, the Greek prefix corresponding to the number of carbon atoms in the molecule. The first four members of the alkane series do not use the Greek... 

Numbers of ligands are indicated by Greek prefixes di-, tri-, tetra-, penta-, hexa-, hepta-, octa-, nona- (ennea-), deca-, etc. If, however, the names of the ligands themselves already contain these prefixes (e.g., diethyl-enefnamine), the ligand name is placed in parentheses and the prefix outside becomes bis-, tris-, tetrakis-, pentakis-, hexakis-, etc. 

Use of nmftlpBcative prefixes. The proportions of the constituents, be they mono-atomic or polyatomic, may be indicated by numerical prefixes (mono-, di-. tri-. lelra-, penta-. etc.) as detailed in [Table 1-3]. These precede the names they modify. Joined... 

Indicate how many of each element is present with a prefix multiplier (mono = 1 di = 2 tri = 3 tetra = 4 penta = 5 hexa = 6 hepta = 7 octa = 8)... 

Table C Metric Multipliers tera, peta, exa come from tetra, penta, hexa with one letter removed zetta, yotta come from zeta, iota, with one letter added atto comes from Danish "atten" for 18 zepto comes from Latin "septem" or Greek "hepta" (1000 7) and yocto comes from Greek "octo" (1000-8) with one prefix letter added...

The ligands include one Cl- ion and five NH3 molecules. The chloride ion is designated as chloro, and each ammonia molecule is designated ammine. The prefix penta- indicates that there are five NH3 ligands present. The name of the complex cation is therefore pentaamminechloro-cobalt(III). Note that the ligands are named alphabetically, disregarding the prefix. Since the counter ions are chloride ions, the compound is named as a chloride salt ... 

But nearly every alkane can have a number of isomeric structures, and there must be an unambiguous name for each of these isomers. The butanes and pentanes are distinguished by the use of prefixes w-butane and isobutan penta, isopentane and neopentane. But there are 5 hexane T lTieptanes, and 75 decanes it would be diflicnli to devise, and even more difficult to remember, a different prefix for each of these isomers. It is obvious that some systematic method of naming is needed. 

From the formula P2O5, two phosphorus atoms and five oxygen atoms make up a molecule of the compound. From Table 9-1, di-is the prefix for two, and penta- is the prefix for five, diphosphorus pentoxide. 

If more than one alkyl group of the same type is attached to the chain, use the prefixes di- (two), tri- (three), tetra- (four), penta- (five), and so forth to specify the total number of such attached groups in the molecule. Thus, 2,2,3-trimethylbutane has two methyl groups attached to the second carbon atom and one to the third carbon atom of the four-atom butane chain. It is an isomer of heptane (CyHig). 

The stoichiometric name of the compound is then formed by combining the name of the electropositive constituent, cited first, with that of the electronegative constituent, both suitably qualified by any necessary multiplicative prefixes ( mono , di , tri , tetra , penta , etc., given in Table IV). The multiplicative prefixes precede the names they multiply, and are joined directly to them without spaces or hyphens. The final vowels of multiplicative prefixes should not be elided (although monoxide , rather than monooxide , is an allowed exception because of general usage). The two parts of the name are separated by a space in English. 

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