The Physical Properties of Alkanes, Alkyl Halides, Alcohols, Ethers, and Amines

Predict the approximate size of the following bond angles. (Hint See Sections 1.11 and 1.12.) 

9 THE PHYSICAL PROPERTIES OF ALKANES, ALKYL HALIDES, ALCOHOLS, ETHERS, AND AMINES 

Now we will look at the physical properties of the five families of compounds whose names and structures we have just examined. Comparing the physical properties of several families of compounds makes learning them a little easier than if the physical properties of each family were presented separately. 

Alkanes contain only carbons and hydrogens. Because the electronegativities of carbon and hydrogen are similar, the bonds in alkanes are nonpolar—there are no significant partial charges on any of the atoms. Alkanes, therefore, are neutral, nonpolar molecules, so the attractive forces between them are relatively weak. The nonpolar nature of alkanes gives them their oily feel. 

However, it is only the average charge distribution over the alkane molecule that is neutral. Electrons move continuously, and at any instant the electron density on one side 

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The Physical Properties of Alkanes, Alkyl Halides, Alcohols, Ethers, and Amines 113... 

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