Suppose you have a sample of benzoic acid dissolved in water.


b. Now assume that aqueous NaOH is added to the benzoic acid solution until pH 12 is reached. Draw the structure of the major organic species present.

Verified step by step guidance

1. Identify the chemical structure of benzoic acid, which is C6H5COOH.
2. Understand that benzoic acid is a weak acid and can donate a proton (H+) to form its conjugate base, benzoate ion (C6H5COO-).
3. Recognize that NaOH is a strong base and will react with benzoic acid to form water and the benzoate ion.
4. At pH 12, the solution is highly basic, indicating that the benzoic acid will be fully deprotonated to form the benzoate ion.
5. Draw the structure of the benzoate ion, which is C6H5COO-, showing the carboxylate group (COO-) attached to the benzene ring.

Key Concepts

Benzoic Acid

Benzoic acid is a simple aromatic carboxylic acid with the formula C6H5COOH. It is characterized by a benzene ring attached to a carboxyl group (-COOH). In aqueous solutions, benzoic acid can partially dissociate to form benzoate ions (C6H5COO-) and protons (H+), depending on the pH of the solution.

pH and Acid-Base Reactions

pH is a measure of the acidity or basicity of a solution, with lower values indicating higher acidity. When NaOH, a strong base, is added to benzoic acid, it reacts to neutralize the acid, forming water and benzoate ions. At pH 12, the solution is highly basic, leading to the complete deprotonation of benzoic acid, resulting in the predominant presence of benzoate ions.

Organic Species in Aqueous Solutions

In aqueous solutions, the major organic species present depend on the pH and the chemical equilibrium of the system. At pH 12, benzoic acid is fully deprotonated, and the major species is the benzoate ion (C6H5COO-). Understanding the structure of these species is crucial for predicting their behavior in chemical reactions and their interactions in biological systems.