Straight Chain Alkanes: Predicting Properties
Straight chain alkanes are compounds with a non-branched backbone of carbon atoms. In addition, as many hydrogen atoms as possible are attached to each carbon atom. Straight chain alkanes are “saturated” hydrocarbons, which means they are completely filled up with hydrogen. See Figure 1 for examples of straight chain, branched chain, saturated, and unsaturated hydrocarbons. Methylene With the exceptions of methane and ethane, straight chain alkanes differ in the number of methylene groups (CH₂) each contains. Thus the first five hydrocarbons, methane, ethane, propane, butane, and pentane are written, CH₄ CH₃CH₃ CH₃CH₂CH₃ CH₃CH₂CH₂CH₃ CH₃CH₂CH₂CH₂CH₃ Another method of writing straight chain alkane chemical formulas for the butane and pentane structures above is, CH₃(CH₂)₂CH₃ CH₃(CH₂)₃CH₃ General Formula From this, we can formulate the rule for the formula of a straight chain alkane…