In aqueous chemistry, which process describes ions from dissolved salts reacting with water to generate acidity or alkalinity of the solution?

Introduction / Context:
Solutions of salts can be acidic, basic, or neutral. The phenomenon responsible for producing acidity or alkalinity when salt ions interact with water is crucial in water treatment, buffer design, and environmental chemistry. Distinguishing hydrolysis from other terms like hydration, electrolysis, and dialysis avoids conceptual errors.

Given Data / Assumptions:

• Water is the solvent, salts are the solutes.
• We consider acid–base behavior arising from ion–water reactions at ambient conditions.

Concept / Approach:
Hydrolysis is the reaction of an ion (often the conjugate base of a weak acid or the conjugate acid of a weak base) with water to produce hydroxide or hydronium ions, shifting pH away from neutrality. For example, acetate ion reacts as CH3COO− + H2O ⇌ CH3COOH + OH− (basic solution), whereas ammonium reacts as NH4+ + H2O ⇌ NH3 + H3O+ (acidic solution). Hydration merely denotes water molecules coordinating around ions without changing pH significantly; electrolysis involves electrical decomposition; dialysis is membrane separation and not a chemical pH-generating reaction.

Step-by-Step Solution:

Verification / Alternative check:
pH predictions from K_a, K_b, and K_w relations for salt solutions are all derived from hydrolysis equilibria of the ions involved.

Why Other Options Are Wrong:

• Hydration: solvation only; minimal pH effect.
• Electrolysis: external current; not salt–water acid/base chemistry.
• Dialysis: separation, not reaction.
• Peptization: dispersion of particles, unrelated to pH from salts.

Common Pitfalls:
Calling any ion–water interaction “hydration”; reserve “hydrolysis” for reactions that alter pH via H3O+ or OH− generation.

Final Answer:
hydrolysis