C-C and C-H bonds are considered non-polar.
Complete combustion happens when oxygen in excess, this is the main form of combustion
Incomplete combustion occurs in a limited supply of oxygen.
Alkanes undergo substitution reactions.
In terms of halogens, we only care about $Cl_2,Br_2,I_2$ for organic chemistry, as they have colours in their aqueous form which we can use to identify reactions.
