Polarity of functional group

Polarity of functional group The 0—H bond is very polar. As the number of carbon atoms in an alcohol becomes larger, the alkyl group s non-polar nature becomes more important than the polar 0—H bond. Therefore small alcohols are more polar than alcohols with large hydrocarbon portions. 

Polarity of functional group The bent shape around the oxygen atom in an ether means that the two C—0 dipoles do not counteract each other. Because a C—0 bond is less polar than an 0—H bond, an ether is less polar than an alcohol. 

Polarity of functional group C—N and N—H bonds are polar. Thus, amines are usually polar. 

Polarity of functional group The C=0 bond is polar, so aldehydes and ketones are usually polar. 

Polarity of functional group Due to the presence of the polar 0-H and C=0 bonds, carboxylic acids are polar compounds. 

Polarity of functional group Like carboxylic acids, esters are usually polar molecules. 

Polarity of functional group Because the nitrogen atom attracts electrons more strongly than carbon or hydrogen atoms, the C-N and N-H bonds are polar. As a result, the physical properties of amides are similar to the physical properties of carboxylic acids. 

TABLE 5-4. Approximate Order of the Polarity of Function Groups in Liquid-Solid Chromatography... 

C. The increase in melting and boiling points of organic compounds is related to the polarity of functional groups. 

Adsorption techniques are used a great deal with surfactants, since the wide range of polarity of functional groups of the various classes makes adsorption suitable for separation of the surfactants from each other (Tables 6-9). As a general rule, the quantity of surfactant adsorbed from water onto a substrate increases with increasing salt content of the water, and decreases with higher hydrophilicity of the surfactant (43). Most references to adsorption methods for isolating surfactants from water and wastewater are located in the tables of Chapter 18 on environmental analysis. 

A variety of mechanisms or forces can attract organic chemicals to a soil surface and retain them there. For a given chemical, or family of chemicals, several of these mechanisms may operate in the bonding of the chemical to the soil. For any given chemical, an increase in polarity, number of functional groups, and ionic nature of the chemical can increase the number of potential sorption mechanisms for the chemical. 

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