Note 37 — Chapter VIII · CARBON AND THE HYDROCARBONS

Although the methods of formation and the reactions connected with hydrocarbons are not described in this work, because they are dealt with in organic chemistry, yet in order to clearly show the mechanism of those transformations by which the carbon atoms are built up into the molecules of the carbon compounds, we here give a general example of reactions of this kind. From marsh gas, CH4, on the one hand the substitution of chlorine or iodine, CH3Cl, CH3I, for the hydrogen may be effected, and on the other hand such metals as sodium may be substituted for the hydrogen, e.g. CH3Na. These and similar products of substitution serve as a means of obtaining other more complex substances from given carbon compounds. If we place the two above-named products of substitution of marsh gas (metallic and haloid) in mutual contact, the metal combines with the halogen, forming a very stable compound—namely, common salt, NaCl, and the carbon groups which were in combination with them separate in mutual combination, as shown by the equation:

CH₃Cl + CH₃Na = NaCl + C₂H₆.

This is the most simple example of the formation of a complex hydrocarbon from these radicles. The cause of the reaction must be sought for in the property which the haloid (chlorine) and sodium have of entering into mutual combination.