Based on net result, the types of reactions are:
1. Substitution - an incoming atom or group of atoms replaces a leaving atom or group of atoms
AB + CD → AC + BD
a. Nucleophilic Substitution - an atom or group of atoms in a molecule is replaced by a nucleophile
i. SN1 or Unimolecular Nucelophilic Substitution
ii. SN2 or Bimolecular Nuceleophilic Substitution
b. Electrophilic Substitution - an electrophile attacks the carbanion of the substrate substitutiong one of the hydrogens or other groups
2. Addition - a molecule adds across a pi bond
A + B → C
3. Elimination - one molecule is lost to give a pi bond
AB → A + B
4. Rearrangement - constitutional change in carbon skeleton
Based on mechanism, reaction types are:
1. Polar Reactions - involves heterolytic bond cleavage (heterolytic - uneven breakage: all electrons go to one atom)
2. Radical Reactions - involves homolytic bond cleavage (homolytic - even breakage: one electron goes to each atom)
