Alkanes are generally unreactive except for and reaction with

Alkanes are generally unreactive due to the strong single covalent bonds between the carbon atoms in their chains. However, they do undergo two main types of reactions:

1. Combustion: Alkanes react with oxygen in a combustion reaction to produce carbon dioxide and water. This reaction is highly exothermic, meaning it releases a lot of energy in the form of heat and light. This is why alkanes are used as fuels. The general equation for this reaction is:

   CnH2n+2 + (3n+1)/2 O2 → n CO2 + (n+1) H2O

2. Substitution: Alkanes can also undergo substitution reactions, where one or more of the hydrogen atoms in the alkane is replaced by another atom or group of atoms. This usually occurs in the presence of UV light or heat. The most common type of substitution reaction is halogenation, where a halogen (like chlorine or bromine) replaces a hydrogen atom. The general equation for this reaction is:

   R-H + X2 → R-X + HX

   (where R represents the rest of the alkane molecule, and X represents a halogen)

These are the main reactions that alkanes undergo, although there are others that can occur under specific conditions.