Which of the following solutions is slightly acidic due to hydrolysis?

Correct option is B

The correct answer is: (B) NH₄Cl

Explanation:

• NH₄Cl (Ammonium chloride) is slightly acidic due to hydrolysis.
• Ammonium chloride is a salt formed from a strong acid (HCl) and a weak base (ammonium hydroxide, NH₄OH). When dissolved in water, ammonium ions (NH₄⁺) hydrolyze to release hydronium ions (H₃O⁺), making the solution acidic.
• This results in an increase in the concentration of H⁺ ions, leading to a slightly acidic solution.

Information Booster:

• Hydrolysis occurs when a salt reacts with water to form acidic or basic solutions. In this case, NH₄⁺ acts as a weak acid.
• Ammonium ions (NH₄⁺) are from a weak base (ammonium hydroxide), which undergoes hydrolysis in water to give off H₃O⁺ (hydronium ions), resulting in an acidic pH.
• Chloride ions (Cl⁻) do not participate in hydrolysis as HCl is a strong acid.

Additional Information:

• NH₄CH₃COO: While ammonium acetate is also a salt of a weak base and weak acid, its pH is slightly neutral or slightly basic, not acidic, because the conjugate base (acetate ion) can neutralize the ammonium ion's acidity.
• Na₂CO₃: Sodium carbonate is basic, as the carbonate ion (CO₃²⁻) is a strong conjugate base of carbonic acid and raises the pH.
• CH₃COONa: Sodium acetate is basic because the acetate ion (CH₃COO⁻) is a weak base that increases the pH.