Alkanes, also known as paraffins, are saturated hydrocarbons that contain only single bonds between carbon atoms. They are one of the simplest and most fundamental families of organic compounds. Alkanes have the general formula CnH2n+2, where n is the number of carbon atoms in the molecule.
Alkanes can be classified into several types, depending on the structure of their molecules:
1. Linear or normal alkanes These alkanes have a straight chain of carbon atoms without branches. Methane (CH4) is the simplest alkane, followed by ethane (C2H6), propane (C3H8), butane (C4H10), and so forth. As the chain lengthens, the formula remains CnH2n+2.
2. Branched alkanes These alkanes have one or more carbon chains attached to the main chain. As molecules become larger, there are more possibilities for the chain to branch into different configurations. A common example is isobutane (Methylpropane), a branched form of butane.
3. Cyclic alkanes Also known as cycloalkanes, these compounds form closed rings of carbon atoms. Cycloalkanes have the general formula CnH2n, because forming a ring requires losing two hydrogens compared to linear or branched alkanes with the same number of carbons. An example is cyclohexane (C6H12).
[1] Linear Alkane (Butane)
[2] Branched Alkane (2-Methylpropane)
[3] Cyclic Alkane (Cyclohexane)
[4] Bicyclic Alkane (Bicyclo[2.2.1]heptane)
Homologous series
Linear alkanes form a homologous series as they only differ in the number of -CH2 groups and can be derived from a general formula: CH3-(CH2)n-CH3
Isomers
Compounds that have the same molecular formula but different structures are called isomers. Butane and 2-methylpropane are isomers with the formula C4H10.
[5] Butane
[6] 2-Methylpropane