Molecular line formula

The Pesticide Index (ref. 14) lists the following categories of pesticides acaricides, attractants, chemosterilants, defoliants, fungicides, herbicides, insecticides, molluscicides, nematicides, plant regulators, repellents, and rodenticides. Listings are in alphabetical order with structural and molecular formulae for single chemical entities. Other data include CAS nomenclature and number Wiswesser Line Notation LD-50 and test animal data when available physical appearance and safety information. Also provided are a CAS nomenclature index separate molecular (line) formulae of chemicals identified by their common names a separate section of Wiswesser line notations, also with common names an appendix of manufacturers, and an appendix of recent publications dealing with pesticide names. 

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... 

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

One of a number of molecular entities having the same atomic composition, but different line formulas and/or different stereochemical configurations. A distinction is usually made between structural isomers (molecular entities have the same atomic composition albeit different line formuls), stereoisomers (entities having different arrangements, usually noninterconvertable and nonsu-perimposable, in space), and cis-trans isomers (having different positions for substituents with respect to double bonds or sides of a ring structure). 

Given a line formula, such as -— (pentane), write the complete structure and clearly show the arrangement of atoms in the molecule. Tell how many hydrogens are attached to each carbon, what the molecular formula is, and what the functional groups are. 

Table 20.2 Systematic Name The First Four Unbranched Alkenes Common Molecular Name Formula Structural Formula Line Formula...

Draw line formulas for two compounds with the molecular formula C5H10 having the live carbon atoms in a continuous chain. Name them. 

Practice Problem 20.1 1 Write line formulas representing all alkynes with the molecular formula 411. ... 

TOMOCOMD TOpological Molecular WLN Wis vesser Line-formula... 

Four types of formulas, each providing different information, are used in organic chemistry the molecular formula, the structural formula, the condensed formula, and the line formula. 

The first part of this table lists substituent groups and their line formulas. A substituent group is defined by lUPAC as a group that replaces one or more hydrogen atoms attached to a parent structure. Such groups are sometimes called radicals, but lUPAC now reserves the term radical for a free molecular species with unpaired electrons. lUPAC does not recommend some of these names, which are marked here with asterisks (e.g., amyl ), but they are included in this list because they are often encountered in the older literature. Substituent group names which are formed... 

Name Molecular Formula Line Formula Ref. VJcra- Comments... 

Substances are listed alphabetically by systematic name. The Notes column gives further information on the form of the substance and the basis to which the TLV is referred. This column also includes common synonyms and acronyms in brackets (e.g., [MTBE]). The Eormula column gives the molecular formula in the Hill convention for organic compounds and the customary line formula for inorganic compounds. The TWA and STEL limits appear in the last two columns. 

The constitution of a molecule (nmnber of, kind of, and cormectivities of atoms) may be represented by a two-dimensional map in which the interatomic linkages (bonds) are drawn as fines. There are two constitutional isomers that are represented by the molecular formula C2HgO ethanol and dimethyl ether. The differences in cormectivities, which are not evident in the common constitutional inventory C2H O, can be conveyed by t) o-graphical line formulas (CH3CH2OH for ethanol and CH3OCH3 for dimethyl ether), or by structural representations (see Figure 2). As the number and kinds of atoms in substances increase, the number of constitutional isomers increases. 

In the skeletal representations on the right, called a bond-line formula or carbon skeletal diagram, we assume that there is a carbon atom at every vertex and at the end of a line. Hydrogens attached to a vertex or to the end of a line are left out. When atoms that are neither carbon nor hydrogen, termed heteroatoms, are present, hydrogens attached to them are shown, as illustrated in the following examples. The second example is the amino acid isoleucine, which has the molecular formula C6H13NO2. 

The most common type of structural formula used by organic chemists, and the fastest to draw, is the bond-line formula. (Some chemists call these skeletal formulas.) The formula in Fig. 1.3 is a bond-line formula for propyl alcohol. The sooner you master the use of bond-line formulas, the more quickly you will be able to draw molecules when you take notes and work problems. And, lacking all of the symbols that are explicitly shown in dash and condensed structural formulas, bond-line formulas allow you to more quickly interpret molecular connectivity and compare one molecular formula with another. 

Write bond-line formulas for all of the constitutional isomers with the molecular formula C4H8. 

Open computer molecular models for dimethyl ether, dimethylacetylene, and OT-l,2-dichloro-l,2-difluoroethene from the 3D Molecular Models section of the book s website. By interpreting the computer molecular model for each one, draw (a) a dash formula, (b) a bond-line formula, and (c) a three-dimensional dashed-wedge formula. Draw the models in whatever perspective is most convenient—generally the perspective in which the most atoms in the chain of a molecule can be in the plane of the paper. 

Write bond-line formulas for three isomeric compounds that contain a carbonyl group and have the molecular formula C4H8O. Then give their lUPAC names. 

Pentachloroethane ipen-t9- klor- e- than n. CHCI2CCI. Non-flammable solvent. Bp, 161°C vp, 5mmHg per 20°C Sp gr, 1.685. CAS registry number 76-01-7. Additional names Pentalin. Molecular formula C2HCI5. Molecular weight 202.30. Percent composition C 11.87%, H 0.50%, and Cl 87.62%. Line formula CCI3CHCI2. Literature references Toxicity data Bar-soum GS, Saad K (1934). Quart J Pharm Pharmacol 7 205. Properties liquid chloroform-like odor, 1.6712 bp... 

Expand the bond-line formulas of the amino acid cysteine and the neurotransmitter serotonin to show all the unshared electron pairs. Molecular formulas of organic compounds are customarily presented in the fashion CaMbX Yd- Carbon and hydrogen are cited first, followed by the other atoms in alphabetical order. What are the molecular formulas of cysteine and serotonin ... 

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