Introduction
The properties of an organic molecule are determined largely by the reactive part of the molecule. This reactive part is called functional group. Compounds with the same function group
![](https://inspiranotes.com/wp-content/uploads/2023/03/classes_of_compounds-1024x432.png)
Organic compounds can be classified based on active part in the compounds. The active part is called the functional group.
Hydrocarbons: alkanes and alkenes
Alkanes and alkenes are hydrocarbons, i.e. they only contain hydrogens and carbons. Alkanes only contain single carbon – carbon bond, while alkenes contain at least one double carbon – carbon bond.
![class of compound: alkanes and alkenes](https://inspiranotes.com/wp-content/uploads/2023/03/alkane_alkenes-1024x773.png)
Halogenoalkanes and alcohols
In halogenoalkanes
![class of compound: halogenoalkanes and alcohols](https://inspiranotes.com/wp-content/uploads/2023/03/halo_alco-1024x816.png)
Aldehydes and ketones
Both aldehydes and ketones contain carbonyls. In an aldehyde, the carbonyl is at the end of the carbon chain, while in a ketone, the carbonyl is never at the end of the carbon chain.
![class of compound: aldehydes and ketones](https://inspiranotes.com/wp-content/uploads/2023/03/carbonyls-1024x815.png)
Carboxylic acids and esters
Carboxylic acids and esters have the same general formula, CnH2nO2, but different functional groups.
![class of compound: carboxylic acids and esters](https://inspiranotes.com/wp-content/uploads/2023/03/carbox_ester-1024x815.png)
Amines and nitriles
Both amines and nitriles contain nitrogens.
![class of compound: amines and nitriles](https://inspiranotes.com/wp-content/uploads/2023/03/amine_nitrile-1024x816.png)
Test yourself
Checklist
Can I
- define the term hydrocarbon?
- identify the following classes of compounds from the functional group present: alkane, alkene, halogenoalkane, alcohol, aldehyde, ketone, caboxylic acid, ester, amine and nitrile?