Organic reactions generally involve functional groups and happen more slowly than inorganic reactions. There are several types of organic reactions including substitution where atoms or groups replace hydrogens, addition where atoms are added to double or triple bonds, and fermentation where enzymes catalyze reactions. Polymerization reactions form large molecules called polymers from smaller molecule monomers through condensation or addition reactions.

1. Organic Reactions
• Happen slowly compared to inorganic reactions
• Usually just involve the functional groups, leaving the greater parts of the molecules
relatively unchanged
Substitution
• Means replacement of one kind of atom or group
• In hydrocarbons, one or more hydrogens can be replaced by active members of the
halogen family
 This is referred to as halogen substitution of halogenation
Addition
• Usually involves adding one or more atoms at a double or triple bond of an
unsaturated molecule
• This results in the saturation of the compound
• The addition of halogens is still called halogenation
• The addition of hydrogen is called hydrogenation
Fermentation
• In fermentation, enzymes produced by living organisms act as catalysts

2. Combustion
• In order for combustion to take place, two items are needed:
1.) two or more reactants which are unstable
2.) energy to activate the reaction
Esterification
• the reaction of an acid with an alcohol to give an ester and water:
Saponification
• the hydrolysis of fats by bases
Polymerization
• involves the formation of a large molecule from smaller molecules called monomers
Ex.) rubbers, plastics, proteins, starches
Polymer – composed of many repeating units called monomers
Condensation polymers
• result from the bonding of monomers by a dehydration reaction’
• water is a usual by-product

3. Addition polymers
• an addition polymerization results from the joining of monomers of unsaturated
compounds by “opening” double or triple bonds in the carbon chain