Question

4. Which one of the following aqueous solutions, when mixed with an equal volume of 0.10 mol L- aqueous NH3​, will produce a buffer solution? A. 0.10 mol L−1HCl B. 0.20 mol LHCl c. 0.10 mol L−1CH3​COOH D. 0.050 mol LNaOH E. 0.20 mol L−1NH3​Cl

Answer 1

An equal volume of the 0.20 mol L-1 NH4Cl solution will produce a buffer with the given 0.10 mol L-1 NH3 solution, as NH4Cl provides the conjugate acid necessary for the buffering effect.

Step-by-step explanation:

The aquatic solution that will produce a buffer solution when mixed with an equal volume of 0.10 mol L-1 NH3 is option E: 0.20 mol L-1 NH4Cl. A buffer solution consists of a weak acid and its conjugate base or a weak base and its conjugate acid. When equal molar amounts of NH3 (a weak base) and NH4Cl (which provides the conjugate acid NH4+) are mixed, they form a buffer solution that can resist changes in pH.

Answer 2

To make a buffer solution from 0.10 mol L-1 aqueous NH3, you would need a solution containing its conjugate acid. Among the options listed, E. 0.20 mol L-1 NH4Cl contains the conjugate acid NH4+ and thus will create a buffer with NH3.

Step-by-step explanation:

The question asks which aqueous solution, when mixed with an equal volume of 0.10 mol L-1 aqueous NH3, will produce a buffer solution. A buffer solution can be created by mixing a weak acid with its conjugate base, or a weak base with its conjugate acid. In this case, NH3 is a weak base that can form a buffer solution when mixed with its conjugate acid, which is NH4+. Of the options provided, NH4Cl contains the conjugate acid NH4+ and will form a buffer with NH3. Therefore, the answer is E. 0.20 mol L-1 NH4Cl.