Question

Now take a fresh 60 mL of the 0.50 M pH 6.83 buffer and add 3.7 mL of 1.00 M NaOH. Using steps similar to those above, calculate the new pH of the solution.

Answer 1

Answer:

pH = pKa + log (33.7 mm / 26.3 mm)

Explanation:

Initial pH = 6.83

If we add a strong base, we expect that pH would be more alkaline

Initially we have: 60 mL . 0.50M =  30 mmoles of acid

Now, we add the base:

3.7 mL . 1.00 M = 3.7 mmmoles of base

Concentration of acid: 30 mmoles - 3.7 mmoles of base = 26.3 mm

Concentration of salt: 30 mmmoles + 3.7 mmoles of base = 33.7 mm

pH = pka + log (33.7 mm / 26.3 mm)

Information of pKa is missing