Alcohols
Alcohols have the functional group OH. A functional group is a group of atoms that gives the molecule unique chemical properties. Molecules with the hydroxyl group (OH) are very soluble in water, depending on their molecular size. Below is a table of the homologous series of alcohols.
Name
Formula
Structural formula
Methanol
CH3OH
Ethanol
CH3CH2OH
Propanol

CH3CH2CH2OH

Propanol has two forms as does butanol, shown below. 1-propanol and 2-propanol are isomers. That is, they have the same molecular formula but a different structural formula.
Butanol
CH3CH2CH2CH2OH
What about if an alcohol has two hydroxyl groups? Well we count the longest carbon chain that contains the two hydroxyl groups, keep the "e" at the end of parent chain, number the carbons so that they are the lowest possible numbers and use the suffix diol. Lets see some examples  
Ethane-1,2-diol
Pentane-1,2-diol

Keep in mind that it is Ok to write 4-butanol as butan-4-ol. It is up to you. 3-hexanol, for example, can be written as hexan-3-ol.

Why do we not use the names 4-butanol or 3-butanol?
Solution

How many different straight carbon chain isomers of pentanol can you identify? Draw their structural formula.
Solution

Continue with naming alcohols primary as well as secondary and tertiary alcohols
Continue with oxidation reactions of primary and secondary alcohols