Answer:
12.44 mL of 0.1 M acetic acid solution
37.56 mL of 0.1 M sodium acetate solution
Explanation:
To solve this problem we can use Henderson-Hasselbach's equation:
Where [A⁻] and [HA] are the molar concentrations of sodium acetate and acetic acid, respectively.
First we use the equation to calculate the molar concentration ratio in the buffer solution:
We can rewrite the last part, using the definition of molar concentrations (C=n/V):
From the problem we also know that:
We rewirte the equation once again, keeping in mind that the moles of each substance come from the original 0.1 M solutions:
So now we have a system of two equations and two unknowns, we use algebra to solve them:
We replace that value in the other equation:
We use that value in the first equation:
Finally, we use the definition of molarity to calculate the volume of each solution:
