What is the Difference Between Benzoic Acid and Ethyl Benzoate?

Benzoic acid and ethyl benzoate are two different organic compounds with distinct properties. The main differences between them are:

1. Structure: Benzoic acid is a carboxylic acid with the molecular formula C₇H₆O₂, while ethyl benzoate is an ester formed from the condensation of benzoic acid and ethanol, with the molecular formula C₉H₁₀O₂.
2. Sodium Bicarbonate Test: Benzoic acid, being an acid, gives a positive sodium bicarbonate test, producing effervescence of carbon dioxide gas upon reaction with sodium hydrogen carbonate. On the other hand, ethyl benzoate does not react with sodium hydrogen carbonate and gives a negative sodium bicarbonate test.
3. Solubility: Benzoic acid is soluble in water, while ethyl benzoate is insoluble in water and floats on top of it.
4. Color Change with FeCl₃: Neither benzoic acid nor ethyl benzoate exhibits a color change with neutral ferric chloride (FeCl₃) solution.
5. Boiling Point: Benzoic acid has a boiling point of around 360 K, while ethyl benzoate's boiling point is approximately 386 K.
6. Applications: Benzoic acid is used as a food preservative and in the production of various chemical compounds, including plasticizers and perfumes. Ethyl benzoate is commonly used as a flavoring agent due to its sweet, fruity aroma.

Comparative Table: Benzoic Acid vs Ethyl Benzoate

Here is a table comparing the differences between benzoic acid and ethyl benzoate:

Benzoic acid is an aromatic carboxylic acid with the chemical formula C7H6O2, while ethyl benzoate is an aromatic ester with the chemical formula C7H5COOC2H5. Both compounds have a sweet and pleasant odor due to their aromatic nature. Benzoic acid occurs as a colorless crystalline solid, whereas ethyl benzoate is a colorless liquid. The key difference between benzoic acid and ethyl benzoate is the functional group present in each molecule: benzoic acid has a carboxylic acid group (COOH), while ethyl benzoate has an ester group (COO).