A buffer contains significant amounts of ammonia and ammonium chloride. Write equations showing how this buffer neutralizes added acid and added base.

Verified step by step guidance

1. Step 1: Identify the components of the buffer. In this case, the buffer is made up of ammonia (NH3) and ammonium chloride (NH4Cl). Ammonia is a weak base and ammonium ion is its conjugate acid.
2. Step 2: Write the equation for the reaction of the weak base (ammonia) with added acid (H+). The ammonia will react with the added acid to form ammonium ion: NH3(aq) + H+(aq) -> NH4+(aq).
3. Step 3: Write the equation for the reaction of the conjugate acid (ammonium ion) with added base (OH-). The ammonium ion will react with the added base to form ammonia and water: NH4+(aq) + OH-(aq) -> NH3(aq) + H2O(l).
4. Step 4: Understand the buffer action. When acid is added to the buffer, it reacts with the weak base (ammonia) to form its conjugate acid (ammonium ion), thus reducing the increase in H+ concentration. When base is added, it reacts with the conjugate acid (ammonium ion) to form its conjugate base (ammonia), thus reducing the increase in OH- concentration.
5. Step 5: Remember that the ability of the buffer to resist changes in pH depends on the presence of significant amounts of both the weak base and its conjugate acid. In this case, the buffer contains significant amounts of both ammonia and ammonium chloride.

Key Concepts

Buffer Solutions

Buffer solutions are mixtures that resist changes in pH when small amounts of acid or base are added. They typically consist of a weak acid and its conjugate base or a weak base and its conjugate acid. In this case, ammonia (NH3) acts as the weak base, while ammonium chloride (NH4Cl) provides the conjugate acid (NH4+).

Neutralization Reactions

Neutralization reactions occur when an acid reacts with a base to form water and a salt. In the context of a buffer, when an acid is added, the weak base (NH3) will react with the hydrogen ions (H+) from the acid, effectively neutralizing it. Conversely, when a base is added, the conjugate acid (NH4+) will react with the hydroxide ions (OH-) to maintain the pH.

Equilibrium in Buffer Systems

Buffer systems operate based on the principle of chemical equilibrium, where the concentrations of the weak acid and its conjugate base (or weak base and its conjugate acid) adjust to counteract changes in pH. The equilibrium shifts in response to added acids or bases, allowing the buffer to maintain a relatively stable pH, which is crucial for many biological and chemical processes.