Question

Kingsley then adds 44.12 mL of NaOH to 250.00 mL of the HCOOH solution. The neutralization reaction resulted in 0.091 moles of HCOOH and 0.036 moles of HCOO- left in solution. Determine the pH of the resulting solution.

Answer 1

Answer:

pH = 3.34

Explanation:

We can calculate the pH using Henderson-Hasselbach's equation:

• pH = pKa + log$\frac{[HCOO^-]}{[HCOOH]}$

for HCOOH, pKa = 3.75.

We can calculate [HCOO⁻] and [HCOOH] using the given number of moles for each one and the final volume:

• Final Volume = 44.12 mL + 250 mL = 294 mL

• 294 mL / 1000 = 0.294 L

• [HCOO⁻] = 0.036 mol / 0.294 L = 0.122 M

• [HCOOH] = 0.091 mol / 0.294 L = 0.310 M

Then we proceed to calculate the pH:

• pH = 3.75 + log$\frac{0.122}{0.310}$

• pH = 3.34