Alcohols
- Alcohols are colourless liquids that dissolve in water to form neutral solutions
- The first four alcohols are commonly used as fuels
- All alcohols contain the hydroxyl (-OH) functional group which is the part of alcohol molecules that is responsible for their characteristic reactions
A molecule of ethanol
Diagram of the side chain and -OH group in ethanol which characterises its chemistry
- The names and structures of the first four alcohols in the homologous series are shown below
- In terms of naming, the same system is used as for alkanes and alkenes, with the final ‘e’ being replaced with ‘ol’
| Name | Formula | Displayed formula |
| Methanol | CH3OH |  |
| Ethanol | C2H5OH |  |
| Propan-1-ol | C3H7OH |  |
| Butan-1-ol | C4H9OH |  |
Examiner Tip
In your exam it is acceptable to write propan-1-ol and butan-1-ol as propanol and butanol respectively.
The 1 indicates that the -OH group is located on the first carbon atom in the molecule as it is possible to have it located on a different carbon atom, but you do not need to know this for your exam.
