Wurtz reaction - This reaction is employed to obtain higher alkanes from the halides of lower alkanes. The halides of lower alkanes are treated with sodium metal in ether:
$$
\mathrm{RX}+2 \mathrm{Na}+\mathrm{XR}^{1} \stackrel{\text { aws }}{\longrightarrow} \mathrm{R}-\mathrm{R}^{1}+2 \mathrm{Na}-\mathrm{X}
$$
alkyl halide alkyl halide
\(\begin{array}{lc}\mathrm{CH}_{3} \mathrm{l}+2 \mathrm{Na}+\mathrm{CH}_{3} \mathrm{l} \stackrel{\mathrm{Ate}}{\longrightarrow} \mathrm{CH}_{3}-\mathrm{CH}_{3}+2 \mathrm{Nal} \\ \text { (methyl iodide) } & \text { (ethane) }\end{array}\)