Homolytic fission - each bonded atom takes one of the shaired pair of electrons.
Each atom now has an unpaired electron and is called a radical
Two species of the same type are produced: X - Y -------> X. + Y. (2 radicals)
Heterolytic fission - One of the bonded atoms takes both of the shaired pair of electrons.
Two ions are produced:
The atom that takes both shared electrons becomes a negatively charged ion (anion)
The atom that does not take the shared electrons becomes positively charged ion (cation). X - Y ----------> X+ + Y- (2 ions)
Nucelophile is a reactant that attacks an electron deficient carbon atom, donating an electron pair. Are often negative ions with a lone pair of electrons. Often inculde an electronegative atom with a lone pair of electrons and a Negative partial charge
Br-, :OH-, H2O, NH3
Electrophile is a reactant that attacks an area of high electrons density accepting an electron pair. Are often positive ions. Some molecules can act as electrophiles these often include an atom with a positive partial charge.
Br2, HBr, NO2+
Addition -2 reactants combine and make 1 product. Molecule is added across the double bond of an unsaturated molecule to make a saturated molecule.
Substitution - atom or group of atoms is replaced with different atom or group of atoms.
Elimination - 1 reactant to form 1 products. Molecule is removed from saturated molecule to make an unsaturated molecule.