Line formulas

Wiswesser line notation The Wiswesser line-formula notation (WLN) is a method for expressing the more usual graphical structure of a chemical compound as a linear string of symbols. The resulting alternative notation is unambiguous, short and particularly suitable for computer processing and retrieval but can also be understood easily by chemists after minimal training in its use. 

W.J. Wiswesser, A Line-Formula Chemical Notation, Y. Thomas Crowell, New York, 1954. 

E.G. Smith, The Wisivesser Line-Formula Chemical Notation, McGraw-Hill,... 

In these simplified representations called bond line formulas or carbon skeleton dia grams, the only atoms specifically written m are those that are neither carbon nor hydro gen bound to carbon Hydrogens bound to these heteroatoms are shown however... 

Unbranched alkanes are sometimes referred to as straight chain alkanes but as we 11 see m Chapter 3 their chains are not straight but instead tend to adopt the zigzag shape portrayed m the bond line formulas introduced m Section 1 7... 

Bond line formula of n pentane Bond line formula of n hexane... 

Much of the communication between insects involves chemical messengers called pheromones A species of cockroach secretes a substance from its mandibular glands that alerts other cockroaches to its presence and causes them to congregate One of the principal components of this aggregation pheromone is the alkane shown in the bond line formula that follows Give the molecular formula of this substance and represent it by a condensed formula... 

Write condensed and bond line formulas for the five isomeric... 

We can use bond line formulas to represent alkenes in much the same way that we use them to represent alkanes Consider the following alkene... 

Bond line formula (Section 1 7) Formula in which connec tions between carbons are shown but individual carbons and hydrogens are not The bond line formula... 

Chemical Designation - A list of common synonyms is given. Synonym names are alternative systematic chemical names and commonly used trivial names for chemicals. An index of synonyms is provided at the end of the handbook to assist the reader in identifying a particular chemical and researching chemical hazards information in the event that the common name of the chemical is not known. The data field also contains the chemical formula. The chemical formula is limited to a commonly used one-line formula. In the case of some organic chemical compounds it has not been possible to represent the chemical structure within such limitation. 

All five models for ethane show roughly the same information. The Wire model looks like a line formula in your chemistry textbook, except that all atoms, not just earbons, are found at the end of a line or at the intersection of lines. (The only exception occurs where three atoms lie on a line. Here, a Wire model will not show the exact position of the center atom.) The Wire model uses color to distinguish different atoms, and one, two and three lines to indicate single, double and triple bonds, respectively. 

The resonance interaction of chlorine with the benzene ring can be represented as shown in 13 or 14, and both of these representations have been used in the literature to save space. However, we shall not use the curved-arrow method of 13 since arrows will be used in this book to express the actual movement of electrons in reactions. We will use representations like 14 or else write out the canonical forms. The convention used in dashed-line formulas like 14 is that bonds that are present in all canonical forms are drawn as solid lines, while bonds that are not present in all forms are drawn as dashed lines. In most resonance, a bonds are not involved, and only the n or unshared electrons are put in, in different ways. This means that if we write one canonical form for a molecule, we can then write the others by merely moving n and unshared electrons. 

It is relevant to present here some preliminaries as regards the salt bridge, this being a traditionally used and more convenient way than the porous partitioning medium in setting up a laboratory assemblage of an electrochemical cell. In this premise, attention is focused on the line formulae of the two cells as presented below ... 

The two vertical lines in the line formula for each of the cells presented above indicate use of a salt bridge. The first of the two cells has on the left side a combination consisting of zinc and zinc chloride solution at a concentration c1 and on the right side a combination of... 

It is important to discuss cell notation and conventions. Instead of drawing a complete diagram to present electrochemical cells, it is convenient to specify a cell in line formula form or, as may be said, shorthand form. The Cu-Zn cell is thus presented as ... 

For even more convenience in representing the structures of organic compounds, particularly in printed material, line formulas are used, so-called because they are printed on one line. In line formulas, each carbon atom is written on a line adjacent to the symbols for the other elements to which it is bonded. Line formulas show the general sequence in which the carbon atoms are attached, but in order to interpret them properly, the permitted total bond orders of all the respective atoms must be kept in mind. Again referring to the compounds (a) to (e) described above, the line formulas are as follows ... 

If the permitted total bond orders of the respective atoms are remembered, it is apparent that the line formula CH4 cannot represent such structures as... 

The alkane series is also called the saturated hydrocarbon series because the molecules of this class have carbon atoms connected by single bonds only, and therefore have the maximum number of hydrogen atoms possible for the number of carbon atoms. These substances may be represented by the general formula C H2,I + 2 and molecules of successive members of the series differ from each other by only a CH2 unit. The line formulas and names of the first 10 members of the series, given in Table 21-2, should be memorized because these names form the basis for naming many other organic compounds. It should be noted that the first parts of the names of the later members listed are the... 

Number of C Atoms Molecular Formula Line Formula Name... 

EXAMPLE 21.3. Write the line formulas for butane and for methylpropane, both C4H10. 

Name Line Formula Name Line Formula Structural Formula... 

Write line formulas for (a) dibutyl ether, (b) propyl phenyl ether, and (c) methyl octyl ether. 

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