Determine whether or not the mixing of each pair of solutions results in a buffer. a. 155.0 mL of 0.15 M NH3 ; 175.0 mL of 0.17 M HCl

Verified step by step guidance

1. Identify the components needed for a buffer solution: a weak base and its conjugate acid, or a weak acid and its conjugate base.
2. Recognize that NH3 (ammonia) is a weak base and HCl (hydrochloric acid) is a strong acid.
3. Calculate the moles of NH3 using the formula: moles = concentration (M) × volume (L).
4. Calculate the moles of HCl using the formula: moles = concentration (M) × volume (L).
5. Determine if the reaction between NH3 and HCl will result in a buffer by checking if there is an excess of NH3 after the reaction, which would leave a mixture of NH3 and NH4+ (the conjugate acid).

Key Concepts

Buffer Solutions

A buffer solution is a system that resists changes in pH upon the addition of small amounts of acid or base. It typically consists of a weak acid and its conjugate base or a weak base and its conjugate acid. Buffers maintain pH stability, which is crucial in many chemical and biological processes.

Weak Bases and Strong Acids

In the given question, NH3 (ammonia) is a weak base, while HCl (hydrochloric acid) is a strong acid. When mixed, the weak base can partially neutralize the strong acid, but the resulting solution may not form a buffer unless there is a sufficient amount of the weak base to react with the strong acid.

Stoichiometry of Acid-Base Reactions

Stoichiometry involves the calculation of reactants and products in chemical reactions. In this context, it is essential to determine the moles of NH3 and HCl to assess whether they can react completely or if excess amounts of either component will remain, influencing the ability to form a buffer solution.