Which of the following salts generally forms a neutral aqueous solution?

Correct answer: NaCl

Direct answer: A, NaCl, is correct. A salt formed from a strong acid and a strong base generally gives a neutral aqueous solution. Sodium chloride can be formed from hydrochloric acid and sodium hydroxide: HCl + NaOH → NaCl + H₂O. In water, NaCl separates into Na⁺ and Cl⁻ ions. These ions do not undergo appreciable hydrolysis under ordinary conditions, so the solution is generally close to neutral, with pH near 7. Option B, NH₄Cl, is generally acidic because NH₄⁺ is the conjugate acid of the weak base ammonia and reacts with water to produce hydronium ions. Option C, Na₂CO₃, is basic because carbonate ions react with water to form hydroxide ions. Option D, CH₃COONa, is basic because acetate ions are the conjugate base of the weak acid acetic acid. Memory cue: strong acid plus strong base usually gives a neutral salt; weak-acid or weak-base ions can hydrolyse and change the pH.