Predict the products (if any) of the following acid–base reactions.
(a) acetic acid + ammonia
(b) phthalic acid + excess NaOH
(c) p-toluic acid + potassium trifluoroacetate

Verified step by step guidance

1. Step 1: Understand the nature of acid-base reactions. Acid-base reactions involve the transfer of a proton (H⁺) from the acid to the base. Acids are proton donors, and bases are proton acceptors. Identify the acid and base in each reaction.
2. Step 2: For (a) acetic acid + ammonia: Acetic acid (CH₃COOH) is a weak acid, and ammonia (NH₃) is a weak base. The reaction involves the transfer of a proton from acetic acid to ammonia, forming ammonium ion (NH₄⁺) and acetate ion (CH₃COO⁻). Write the balanced chemical equation: ${\mathrm{CH}3}_{\mathrm{COOH}}+{\mathrm{NH}}_3\to {\mathrm{CH}}_3{\mathrm{COO}}_{-}+{\mathrm{NH}}_4+$
3. Step 3: For (b) phthalic acid + excess NaOH: Phthalic acid is a diprotic acid (C₆H₄(COOH)₂). In the presence of excess NaOH, both acidic protons are neutralized, forming the disodium salt of phthalic acid (C₆H₄(COONa)₂) and water. Write the balanced chemical equation: ${C6}_{H_4}+2{\mathrm{NaOH}}_{\to }{C6}_{H_4}$
4. Step 4: For (c) p-toluic acid + potassium trifluoroacetate: p-Toluic acid (C₆H₄(CH₃)(COOH)) is a weak acid, and potassium trifluoroacetate (CF₃COOK) is a weak base. The reaction involves the transfer of a proton from p-toluic acid to trifluoroacetate ion (CF₃COO⁻), forming trifluoroacetic acid (CF₃COOH) and the potassium salt of p-toluic acid (C₆H₄(CH₃)(COOK)). Write the balanced chemical equation: ${C6}_{H_4}+{\mathrm{CF}3}_{{\mathrm{COOK}}_{\to }}$
5. Step 5: Verify the products for each reaction. Ensure that the acid donates a proton to the base, and the resulting conjugate acid and conjugate base are correctly identified. Confirm that the stoichiometry of each reaction is balanced.

Key Concepts

Acid-Base Theory

Acid-base theory explains the behavior of acids and bases in chemical reactions. According to the Brønsted-Lowry theory, acids are proton donors while bases are proton acceptors. Understanding this concept is crucial for predicting the products of acid-base reactions, as it helps identify which species will donate or accept protons during the reaction.

Neutralization Reactions

Neutralization reactions occur when an acid reacts with a base to produce water and a salt. In the context of the given question, recognizing that acetic acid and ammonia will form ammonium acetate, and phthalic acid with NaOH will yield a salt and water, is essential for predicting the products of these reactions.

Functional Groups and Reactivity

The reactivity of organic compounds is largely determined by their functional groups. For instance, carboxylic acids (like acetic and phthalic acid) can donate protons, while amines (like ammonia) can accept them. Understanding the specific functional groups involved in the reactions allows for accurate predictions of the products formed, such as the formation of salts or other derivatives.