Alkanes can indeed undergo substitution reactions. In a substitution reaction, one or more hydrogen atoms in an alkane are replaced by other atoms or groups. Common examples include halogenation, where hydrogen atoms are replaced by halogen atoms like chlorine or bromine.
Alkanes readily undergo combustion reactions in the presence of oxygen. In combustion, alkanes react with oxygen to produce carbon dioxide and water, releasing a large amount of heat energy. This is one of the key uses of alkanes as fuels.
Alkanes can undergo hydrogenation reactions, where hydrogen gas (H2) is added to an alkane in the presence of a suitable catalyst, typically to produce saturated hydrocarbons (alkanes). This is a common industrial process.
Alkanes generally do not undergo addition reactions easily. Addition reactions are more typical of alkenes and alkynes, which have carbon-carbon double or triple bonds. Alkanes, being saturated hydrocarbons, do not have such reactive functional groups.
The correct option is D. Addition. Under suitable conditions, alkanes do not readily undergo addition reactions. These reactions are more characteristic of alkenes and alkynes.