Alkyl halides physical properties

Physical Properties of Alcohols and Alkyl Halides Intermolecular Forces... 

PHYSICAL PROPERTIES OF ALCOHOLS AND ALKYL HALIDES INTERMOLECULAR FORCES... 

Aryl halides resemble alkyl halides m many of their physical properties All are practi cally insoluble m water and most are denser than water... 

Some recent studies have underlined the effect that certain physical properties of the reaction medium have in governing the nature and yields of the products obtained when indole Grignard reagents react with alkyl or alkynyl halides. Such factors include the basicity and dielectric constant of the medium and its ability to solvate any of the reacting species. ... 

Cyclic enone, 12 185 Cyclic ethers, 10 567, 569 12 663 polymerization, 14 271 Cyclic fatigue, in ceramics, 5 633-634 Cyclic gas generators, 6 786-787, 789, 827 Cyclic halides, 19 56 Cyclic hexakis(thio-l,4-phenylene), melt polymerization of, 23 705 Cyclic hydrocarbons, 13 687 Cyclic hydroxyalkyl alkyl peroxide, 18 454 Cyclic ion exchange operation, 14 408-413 Cyclic ketones, 12 176, 177 14 590-592. See also Cyclic 1,2-diketones physical properties of, 14 591t hydroxyalkyl hydroperoxides from, 18 450... 

In this section, you learned how to recognize, name, and draw members of the alcohol, alkyl halide, ether, and amine families. You also learned how to recognize some of the physical properties of these compounds. In the next section, you will learn about families of organic compounds with functional groups that contain the C=0 bond. 

Analytical data on the soluble products isolated from chloroform are in excellent agreement with the composition 1 Ni+2 1 monoalkylated ligand 1 I or Br. The magnetic moment of this methylated complex was found to be 1.89 Bohr magnetons per nickel (II). The molar conductivities of the methylated and benzylated complexes in methanol at 25° C. are 75.4 and 68.4 ohm-1, respectively. These values approximate those expected for uni-univalent electrolytes in this solvent. The formulation of these alkylated compounds as dimeric electrolytes (structure VII) does not appear to be totally consistent with their physical properties. One or both halide ions may be bound to the metal ion. These results lead to the easily understood generalization that terminal sulfur atoms alkylate more readily than bridged mercaptide groups. 

ZIEGLER-NATTA POLYMERIZATION. Polymerization of vinyl monomers under mild conditions using aluminum alkyls and TiCL lor other transition element halide) catalyst to give a stereoregulated, or tactic, polymer. These polymers, in which the stereochemistry of the chain is not random have very useful physical properties. 

The physical properties of unsubstituted aryl halides are much like those of the corresponding alkyl halides. Thus, boiling points, melting points, and solubilities of aryl halides are very similar to those of alkyl halides containing the same number of carbon atoms. 

Grosse, A.V., Wackher, R.C., Linn, C.B. (1940) Physical properties of the alkyl fluorides and a comparison of the alkyl fluorides with the other halides and with the alkyls of the elements of Period II. J. Phys. Chem. 44, 275-296. 

Organohalides (Figure 1.17) exhibit a wide range of physical and chemical properties. These compounds consist of halogen-substituted hydrocarbon molecules, each of which contains at least one atom of F, Cl, Br, or I. They may be saturated (alkyl halides), unsaturated (alkenyl halides), or aromatic (aryl halides). The most widely manufactured organohalide compounds are chlorinated hydrocarbons, many of which are regarded as environmental pollutants or hazardous wastes. 

The carbon-halogen bond is slightly polar. Overall, however, an alkyl halide is not much more polar than an alkane, so the physical properties of an alkyl halide are not very different from those of an alkane of similar molecular weight. For example, the boiling point of 1-chlorobutane (MW = 92.5 g/mol) is 78°C, whereas that of hexane (MW = 86 g/mol) is 69°C. In general, alkyl halides are insoluble in water. Because of the presence of the more massive halogen atom, the alkyl halide may be more dense than water. For example, when dichloromethane, a common laboratory solvent, and water are mixed, two layers are formed, with dichloromethane as the lower layer. 

Q Name alkyl halides, explain their physical properties, and describe their common uses. 

Q Correctly name alkyl halides, summarize their physical properties, and identify them as 1°, 2°, or 3°. 

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