Class names

As also noted in the preceding chapter, it is customary to divide adsorption into two broad classes, namely, physical adsorption and chemisorption. Physical adsorption equilibrium is very rapid in attainment (except when limited by mass transport rates in the gas phase or within a porous adsorbent) and is reversible, the adsorbate being removable without change by lowering the pressure (there may be hysteresis in the case of a porous solid). It is supposed that this type of adsorption occurs as a result of the same type of relatively nonspecific intermolecular forces that are responsible for the condensation of a vapor to a liquid, and in physical adsorption the heat of adsorption should be in the range of heats of condensation. Physical adsorption is usually important only for gases below their critical temperature, that is, for vapors. 

Electrochemical methods may be classified into two broad classes, namely potentiometric metiiods and voltannnetric methods. The fonner involves the measurement of the potential of a working electrode iimnersed in a solution containing a redox species of interest with respect to a reference electrode. These are equilibrium experiments involving no current flow and provide themiodynamic infomiation only. The potential of the working electrode responds in a Nemstian maimer to the activity of the redox species, whilst that of the reference electrode remains constant. In contrast, m voltannnetric methods the system is perturbed... 

The term acjdoin is commonly used as a class name for the symmetrical keto-alcohols RCOCH(OH)R, and the name of the individual compound Is derived by adding the suffix oin to the stem name of the acid to which the acyloin corresponds, e.g., acetoin, propionoin, butyroin, etc. 

Substitutive names are preferred but functional class names are sometimes more convenient or more familiar and are frequently encountered m organic chemistry... 

Functional class names of alcohols are derived by naming the alkyl group that bears the hydroxyl substituent (—OH) and then adding alcohol as a separate word The chain IS always numbered beginning at the carbon to which the hydroxyl group is attached... 

Functional class names are part of the lUPAC system they are not common names... 

Substitutive name 2 Bromohexane Functional class name 1 Methylpentyl bromide... 

The substitutive names of alcohols are derived by replacing the e end mg of an alkane with ol The longest chain containing the OH group becomes the basis for the name Functional class names of alcohols begin with the name of the alkyl group and end m the word alcohol... 

Wnte structural formulas or build molecular models for all the constitutionally isomenc alcohols of molecular formula C5H12O Assign a substitutive and a functional class name to each one and specify whether it is a pnmary secondary or tertiary alcohol... 

Substitutive lUPAC name 1 Methoxyhexane Functional class name Hexyl methyl ether... 

There are no functional class names for aldehydes in the lUPAC system... 

Substitutive name Functional class names 1 Chlorobutane n Butyl chloride or butyl chloride 2 Chlorobutane sec Butyl chloride or 1 methylpropyl chloride... 

Substitutive name Functional class names 1 Butanol n Butyl alcohol or butyl alcohol 2 Butanol sec Butyl alcohol or 1 methylpropyl alcohol... 

Table 1.9 Functional Class Names Used in Radicofunctional Nomenclature 1.22...

In order of decreasing priority for citation of a functional class name, and the prefix for substitutive nomenclature, are the following related compounds ... 

Inspection of this character table, given in Table A. 12 in Appendix A, shows two obvious differences from a character table for any non-degenerate point group. The first is the grouping together of all elements of the same class, namely C3 and C as 2C3, and (t , and 0-" as 3o- . 

Formula Class name Prefix Suffix Radicofunctional form... 

The majority of food enzymes are used as processing aids, and they have no function in the final food. Eor that reason, they do not need to be declared on the label, and will not be present in the final food in any significant amount. A few enzymes, however, are used both as processing aids and as food additives. When used as additives, they must be declared on the food label using the appropriate class name, eg, preservative or antioxidant ... 

Refinery product separation falls into a number of common classes namely Main fractionators gas plants classical distillation, extraction (liquid-liquid), precipitation (solvent deasphalting), solid facilitated (Parex(TM), PSA), and Membrane (PRSIM(TM)). This list has been ordered from most common to least common. Main fractionators are required in every refinery. Nearly every refinery has some type of gas plant. Most refineries have classical distillation columns. Liquid-liquid extraction is in a few places. Precipitation, solid facilitated and membrane separations are used in specific applications. 

Substitutive lUPAC name l-(Methylthio)hexane Functional class name Hexyl methyl sulfide... 

Cer-erde, /. cerium earth (class name), -erz, n cerium ore, esp. eerite. -feuerzeug, n. m. cerium lighter. 

Ytter-erde, /. yttria (as class name) yttrium earth, -flussspat, m. yttrocerite, ytterhaltig, a. contammg yttrium, yttriferous, yttric. 

Use of hyphens single- and multiple-word names. The general rule is to determine whether the parent is itself an element or compound. If so, then the name is written as a single word if not, then the name is written as multiple words. Methylbenzene is written as one word, for instance, because the parent—benzene—is itself a compound. Diethyl ether, however, is written as two words because the parent—ether—is a class name rather than a compound name. Some further examples follow ... 

Electrophilic aromatic hydrogen exchange reactions fall into two classes, namely those reactions catalysed by acid and those reactions catalysed by base. Of these the former are by far the most common and have been subjected to the most extensive and intensive kinetic studies. 

Earlier, Ahland and coworkers56 noticed that metal and metallic salts which form complexes with Lewis bases can be divided into two classes, namely one which interacts mostly with the donors bearing a first row element as a center and a second which coordinates preferentially with those of second and third row elements. 

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