NH4Cl

Definition

NH4Cl, or ammonium chloride, is a chemical compound composed of the ammonium cation (NH4+) and the chloride anion (Cl-). It is a white crystalline salt that is commonly used in various applications, including as a component in the hydrolysis of salts.

5 Must Know Facts For Your Next Test

1. NH4Cl is a salt that undergoes hydrolysis in water, producing a weakly acidic solution.
2. The hydrolysis of NH4Cl involves the reaction of the ammonium ion (NH4+) with water to form ammonia (NH3) and a hydronium ion (H3O+).
3. The hydrolysis of NH4Cl results in a solution with a pH less than 7, indicating an acidic environment.
4. The extent of hydrolysis for NH4Cl is determined by the equilibrium constant (Kh) for the hydrolysis reaction.
5. The hydrolysis of NH4Cl is an important concept in understanding the behavior of salts in aqueous solutions and their impact on pH.

Review Questions

• Explain the hydrolysis reaction of NH4Cl in water and its impact on the pH of the solution.
  • The hydrolysis of NH4Cl in water involves the reaction of the ammonium ion (NH4+) with water to form ammonia (NH3) and a hydronium ion (H3O+). This reaction can be represented as: NH4+ + H2O ⇌ NH3 + H3O+. The formation of the hydronium ion results in a solution with a pH less than 7, indicating an acidic environment. The extent of hydrolysis and the resulting pH are determined by the equilibrium constant (Kh) for the reaction, which reflects the relative strengths of the conjugate acid-base pair involved.
• Analyze the role of the ammonium ion (NH4+) and the chloride ion (Cl-) in the hydrolysis of NH4Cl.
  • In the hydrolysis of NH4Cl, the ammonium ion (NH4+) acts as the conjugate acid of the weak base ammonia (NH3), while the chloride ion (Cl-) acts as the conjugate base of the strong acid hydrochloric acid (HCl). The hydrolysis reaction involves the ammonium ion reacting with water to produce ammonia and a hydronium ion, which leads to the acidic nature of the resulting solution. The chloride ion, being the conjugate base of a strong acid, does not undergo significant hydrolysis and has a minimal impact on the pH of the solution. The relative strengths of the conjugate acid-base pair, as well as the equilibrium constant (Kh), determine the extent of hydrolysis and the final pH of the NH4Cl solution.
• Evaluate the importance of understanding the hydrolysis of NH4Cl in the context of aqueous salt solutions and their pH properties.
  • Understanding the hydrolysis of NH4Cl is crucial in the broader context of aqueous salt solutions and their pH properties. The hydrolysis of salts, such as NH4Cl, can significantly impact the pH of the resulting solution, which is an important consideration in various chemical and biological processes. Knowing how the ammonium ion (NH4+) and chloride ion (Cl-) behave during hydrolysis allows for the prediction and manipulation of the pH in aqueous systems. This knowledge is particularly relevant in areas like water treatment, pH regulation in biological systems, and the design of buffer solutions. By comprehending the principles governing the hydrolysis of NH4Cl and other salts, chemists and scientists can better understand and control the pH-dependent properties of aqueous solutions, which is essential for a wide range of applications.

Related terms

Ammonium Ion:

The ammonium ion (NH4+) is a positively charged ion formed when ammonia (NH3) accepts a hydrogen ion (H+) in an aqueous solution.

Chloride Ion: The chloride ion (Cl-) is a negatively charged ion that is the conjugate base of hydrochloric acid (HCl).

Hydrolysis:

Hydrolysis is a chemical reaction in which a molecule is cleaved into two or more smaller molecules by the addition of water.