24 mL of 0.39 mol/L acetic acid is titrated with a standardized 0.33 mol/L KOH solution. Calculate the pH of the solution after 17 mL of the KOH solution has been added. Assume the Ka of acetic acid is 1.8 x 10-5.

duplicate post.

A volume of 100 of 1.00 solution is titrated with 1.00 solution. You added the following quantities of 1.00 to the reaction flask. Classify the following conditions based on whether they are before the equivalence point, at the equivalence point, or after the equivalence point.

To calculate the pH of the solution after adding the KOH solution, we need to determine the concentration of acetic acid left in the solution. This can be done by calculating the number of moles of acetic acid initially present and subtracting the number of moles of KOH that have reacted.

1. Calculate the number of moles of acetic acid initially present:
moles of acetic acid = volume of acetic acid (in L) × concentration of acetic acid (in mol/L)
moles of acetic acid = 0.024 L × 0.39 mol/L
moles of acetic acid = 0.00936 mol

2. Calculate the number of moles of KOH that reacted:
moles of KOH = volume of KOH (in L) × concentration of KOH (in mol/L)
moles of KOH = 0.017 L × 0.33 mol/L
moles of KOH = 0.00561 mol

3. Calculate the moles of acetic acid remaining:
moles of acetic acid remaining = moles of acetic acid initially present - moles of KOH that reacted
moles of acetic acid remaining = 0.00936 mol - 0.00561 mol
moles of acetic acid remaining = 0.00375 mol

4. Calculate the concentration of acetic acid remaining:
volume of solution = volume of acetic acid + volume of KOH
volume of solution = 0.024 L + 0.017 L
volume of solution = 0.041 L
concentration of acetic acid remaining = moles of acetic acid remaining / volume of solution
concentration of acetic acid remaining = 0.00375 mol / 0.041 L
concentration of acetic acid remaining = 0.0915 mol/L

5. Calculate the pKa value:
pKa = -log10(Ka)
pKa = -log10(1.8 × 10^-5)
pKa = 4.74

6. Use the Henderson-Hasselbalch equation to calculate the pH:
pH = pKa + log10(concentration of acetate ion / concentration of acetic acid)
The concentration of acetate ion can be determined by subtracting the concentration of acetic acid remaining from its initial concentration:
concentration of acetate ion = concentration of acetic acid initially - concentration of acetic acid remaining
concentration of acetate ion = 0.39 mol/L - 0.0915 mol/L
concentration of acetate ion = 0.2985 mol/L

Now, substitute the values into the Henderson-Hasselbalch equation:
pH = 4.74 + log10(0.2985 mol/L / 0.0915 mol/L)
pH = 4.74 + log10(3.2612)
Using a calculator, the log10(3.2612) is approximately 0.5128
pH = 4.74 + 0.5128
pH = 5.2528

Therefore, the pH of the solution after adding 17 mL of the KOH solution is approximately 5.2528.