Hydrolysis is the breaking down of molecules by water. This word is derived from two words: hydro and lysis. Hydro means water; lysis, in this case, refers to 'to disintegrate'. You're probably still wondering what in the world hydrolysis means. We know that ionic molecules, or salts, consist of cations and anions linked with an ionic bond. So when an ionic molecule is dissolved in water, it gets ionized into its respective cation and anion, and these ions get hydrolyzed by water. Anions of strong acids and cations of strong bases do not get hydrolyzed by water. They are not strong enough to form bonds with water ions, namely hydronium (H₃O⁺) and hydroxide (OH⁻). Therefore hydrolysis is separated into two categories: partial and total hydrolysis. Salts like NaCl, KBr, and CaSO₄ do not get hydrolyzed in water. Their ions are components of strong bases and acids. These salts have a neutral pH whenever they get dissolved in water. Salts like NH₄Cl and K₂CO₃ only get partially hydrolyzed in water. One of their ions makes up a strong acid/base, while the other ion makes up a weak base/acid. The ions which make up a weak base/acid will get hydrolyzed, and depending on the water ion formed, it can be an acidic or basic solution. A combination of a strong acid and a weak base will create an acid salt and vice versa. Finally, salts like NH₄F, CuCl₂, or ZnS completely get hydrolyzed in water. Both their cations and anions make up weak bases and weak acids. These salts can be acidic, neutral, or basic, depending on their acid (Ka) and base (Kb) constants. If a salt's acid constant is greater than its base, it is acidic, and vice versa. Additionally, if its acid equals its base constant, it is a neutral salt. Salt hydrolysis example: NH₄OH(aq) + HCl(aq) → NH₄Cl(aq) + H₂O(l) NH₄Cl(aq) ↔ NH₄⁺(aq) + Cl⁻(aq) NH₄⁺(aq) + H₂O(l) ↔ NH₄OH(aq) + H⁺(aq) I hope this post increased your knowledge of hydrolysis! I apologize if there are any notation, grammar, or spelling mistakes. I've researched various sources, so I hope none of the information presented here is false. If there is, I will immediately correct it.
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Wow! Very Informative. You definitely did your research, I'm quite curious as to how you know such information, I can only say that you must've been learning for a good amount of time. I'm very impressed!