1. Hydrolysis:
* When ammonium chloride dissolves in water, it dissociates into ammonium ions (NH₄⁺) and chloride ions (Cl⁻).
* The ammonium ion (NH₄⁺) undergoes hydrolysis, reacting with water molecules to form hydronium ions (H₃O⁺) and ammonia (NH₃):
```
NH₄⁺(aq) + H₂O(l) ⇌ H₃O⁺(aq) + NH₃(aq)
```
* The production of hydronium ions (H₃O⁺) is what makes the solution acidic.
2. Chloride ions:
* Chloride ions (Cl⁻) are the conjugate base of a strong acid (HCl). They are very weak bases and do not significantly contribute to the pH of the solution.
3. Overall effect:
* Due to the hydrolysis of ammonium ions, the solution becomes acidic. The pH of an ammonium chloride solution will be less than 7.
Other properties:
* Ammonium chloride is a white crystalline solid that is highly soluble in water.
* It is used in various applications, including fertilizers, explosives, and as a food additive.
In summary:
Ammonium chloride behaves as an acidic salt in water because the ammonium ions undergo hydrolysis, producing hydronium ions and making the solution acidic.
