Alkanoic Acids (Carboxylic Acids)

 - Alkanoic acids, also known as carboxylic acids, have the general molecular formula:  

  C(n)H(2n+1)COOH 

- They are sometimes called fatty acids because they occur naturally in fats and oils.  

- The first member of this group is methanoic acid (formic acid), followed by ethanoic acid, propanoic acid, butanoic acid, and pentanoic acid.  

Classification of Alkanoic Acids  

1. Monocarboxylic Acids  

- Contain one carboxyl group (-COOH) per molecule.  

- Examples: Methanoic acid, Ethanoic acid, Propanoic acid.  

2. Dicarboxylic Acids  

- Contain two carboxyl groups per molecule.  

- Examples:  

  - Cis‑butenedioic acid (Maleic acid)  

  - Ethanedioic acid (Oxalic acid)  

  - 2,3‑dihydroxybutanedioic acid (Tartaric acid)  

3. Tricarboxylic Acids 

- Contain three carboxyl groups per molecule.  

- Examples:  

  - 2‑hydroxypropane‑1,2,3‑tricarboxylic acid (Citric acid)  

4. Aromatic Carboxylic Acids 

- Carboxyl group attached to an aromatic ring.  

- Examples:  

  - Benzoic acid  

  - 2‑hydroxybenzoic acid (Salicylic acid)