Deca 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. 

Prefix deca- kilo- mega- giga- tera- ... 

The value of R changes if we express the ideal-gas equation (Equation (1.13)) with different units. Table 2.3 gives values of R in various other units. We must note an important philosophical truth here the value of the gas constant is truly constant, but the actual numerical value we cite will depend on the units with which we express it. We met a similar argument before on p. 19, when we saw how a standard prefix (such as deca, milli or mega) will change the appearance of a number, so V = 1 dm3 = 103 cm3. In reality, the number remains unaltered. 

Note Where it is desired to specify the chain length in an oligomer, the appropriate Greek prefix (deca, docosa, etc.) may be used. 

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. 

Prefix mono- di- tri- tetra- penta- hexa- hepta- octa- nona- deca-... 

In the formula for a hydrate, the number of water molecules associated with each formula unit of the compound is written following a dot for example, Na2CO3T0H2O. This compound is called sodium carbonate decahydrate. In the word decahydrate, the prefix deca- means ten and the root word hydrate refers to water. Decahydrate means that ten molecules of water are associated with one formula unit of compound. The mass of water associated with a formula unit must be included in molar mass calculations. Hydrates are found with a variety of numbers of water molecules. Table 11-1 lists some common hydrates. 

Nearly all binary molecular compormds involve two nonmetals bonded together. Although many nonmetals can exhibit different oxidation numbers, their oxidation numbers are not properly indicated by Roman numerals or suffixes. Instead, elemental proportions in binary covalent compounds are indicated by using a prefix system for both elements. The Greek and Latin prefixes for one through ten are mono, di, tri, tetra, penta, hexa, hepta, octa, nona, and deca. The prefix mono- is omitted for both elements except in the common name for CO, carbon monoxide. We use the minimum number of prefixes needed to name a compound unambiguously. The final a in a prefix is omitted when the nonmetal stem begins with the letter o we write heptoxide, not heptaoxide. ... 

Prefix deca hecto kilo mega giga tera... 

Binary covaient compound (Type III), so prefixes are used. The a in deca- is sometimes dropped. 

Nearly all of the SI prefixes are multiples or sub-multiples of 1000. However, these are inconvenient for many purposes and so hecto, deca, deci, and centi are also used. 

Most prefixes which make a unit bigger are written in capital letters (M, G, T, etc.), but when they make a unit smaller then lower case (m, n, p, etc.) is used. Exceptions to this are the kilo [k] to avoid any possible confusion with kelvin [K] hecto [h] and deca [da] or [dk]. 

Deca- combining form [ME, ft. L. ft. Gk deka-, dek-y ft. deka] (da). Sl-acceptable prefix meaning x 10. 

Think About It Double-check that the subscripts in the formulas match the prefixes in the compound names (a) 4 = tetra and (b) 4 = tetra and 10 = deca. 

Setup In part (a) there is no prefix for sulfur, so there is only one sulfur atom in a molecule of the compound. Therefore, we will use no prefix for the S in the formula. The prefix tetra- means that there are four fluorine atoms. In part (b) the prefixes tetra- and deca- denote four and ten. respectively. 

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