What is the pH of the solution after 10.0 mL of NaOH is added to the titration of 0.1M HOAc?

Steps to Solve

1. Calculate moles of acetic acid (HOAc)

First, determine the number of moles of acetic acid present in the solution. If you have the concentration (molarity) and volume of the acetic acid, use the formula:
$$ \text{Moles of HOAc} = \text{Concentration} \times \text{Volume} $$

2. Calculate moles of sodium hydroxide (NaOH)

Next, calculate the number of moles of sodium hydroxide added to the solution. Again, use the formula:
$$ \text{Moles of NaOH} = \text{Concentration} \times \text{Volume} $$

3. Determine the reaction completion

In the reaction between acetic acid and sodium hydroxide, they react in a 1:1 ratio: $$ \text{HOAc} + \text{NaOH} \rightarrow \text{NaAc} + \text{H}_2\text{O} $$
Compare the moles of acetic acid with moles of sodium hydroxide to see which one is the limiting reactant.

4. Calculate the remaining moles

If not all moles of one reactant are consumed, calculate the remaining moles left after the reaction.

• If moles of HOAc > moles of NaOH, remaining $ \text{HOAc} = \text{Moles of HOAc} - \text{Moles of NaOH} $
• If moles of NaOH > moles of HOAc, remaining $ \text{NaOH} = \text{Moles of NaOH} - \text{Moles of HOAc} $

5. Calculate the concentration of remaining acid or base

After finding the remaining moles, divide by the total volume of the solution (initial volume of acetic acid + volume of NaOH added) to find the concentrations.

6. Calculate the pH of the solution

Depending on whether there's excess acetic acid or sodium hydroxide, apply the appropriate formula to find pH:

• If there's excess acetic acid:
  $$ \text{pH} = 14 + \log\left(\frac{K_a \times \text{C}{acetic}}{\text{C}{NaOH}}\right) $$
• If there's excess sodium hydroxide:
  $$ \text{pOH} = -\log[\text{OH}^-] \text{ and use } \text{pH} = 14 - \text{pOH} $$