Consider the solutions formed by adding 50 mL of a 1.00 M solution of NH₃ to each of the following beakers:

- Beaker 1: 50 mL of 2.00 M HCl(aq)
- Beaker 2: 50 mL of 0.50 M HCl(aq)
- Beaker 3: 50 mL of 1.00 M NH₄Cl(aq)

Which beaker(s) will contain a buffered solution once the mixing is complete?

1) Beaker 3
2) Beakers 1 and 2
3) Beakers 1 and 3
4) Beakers 2 and 3
5) Beakers 1, 2, and 3

Only beaker 3 will contain a buffered solution after adding 50 mL of 1.00 M NH3 because it consists of 1.00 M NH4Cl, which provides a weak acid-conjugate base pair necessary for a buffer.

Explanation:

The question is asking which beaker(s) will contain a buffered solution after adding 50 mL of a 1.00 M solution of NH3 to various solutions. A buffered solution typically consists of a weak acid and its conjugate base, or a weak base and its conjugate acid, and it resists changes in pH when small amounts of acid or base are added.

In beaker 1, we have 50 mL of 2.00 M HCl mixed with 50 mL of 1.00 M NH3. This is not a buffered solution because HCl is a strong acid and will completely react with NH3, leaving no weak base to pair with its conjugate acid.

In beaker 2, we have 50 mL of 0.50 M HCl mixed with 50 mL of 1.00 M NH3. This is also not a buffered solution for the similar reason as beaker 1. However, in this case, since the concentration of NH3 is higher, there would be some excess NH3, but still, it would not form a proper buffer without a significant amount of its conjugate acid NH4+.

In beaker 3, we have 50 mL of 1.00 M NH4Cl mixed with 50 mL of 1.00 M NH3. NH4Cl is a salt that dissociates into NH4+ and Cl-. NH4+ (ammonium ion) is the conjugate acid of NH3 (ammonia), creating a weak acid-conjugate base pair. Thus, beaker 3 will contain a buffered solution.