Functional Groups and Organic Families

A functional group is a small chemical unit consisting of atoms or a group of atoms 

Functional Groups Defining Alkenes, Alkynes, and Aromatic Hydrocarbons 

Aromatic alcohols are called phenols. The simplest phenol, also called phenol, forms when a hydroxyl group replaces a hydrogen atom in the benzene ring. Phenol (carbolic acid) was used as an antiseptic in the 1800s. Today other phenol derivatives are used in antiseptic mouthwashes and in cleaning disinfectants such as Lysol. Phenols are easily oxidized, and this makes them ideal substances to use as antioxidants. By adding phenols such as BHT (butylated hydroxy toluene) and BHA (butylated hydroxy anisole) to food, the phenols oxidize rather than the food. 

Ethers contain an oxygen atom singly bonded to two hydrocarbon units. The func- 

An ether called methyl tert butyl ether (MTBE) has traditionally been used as a fuel oxygenate to reduce toxic air emissions from automobiles  

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