# Exercise 1 | Buffers and Titration of Acids and Bases

Calculate the pH of a solution that is 0.200 M in ammonia NH3 and 0.300 M in ammonium chloride NH4Cl.

Data: Ka (NH4+/NH3) = 5.62 x 10-10

Henderson-Hasselbalch equation can be used:

pH = pKa + log $\frac{{\left[\mathrm{base}\right]}_{0}}{{\left[\mathrm{acid}\right]}_{0}}$

pH = -log (5.62 x 10-10) + log $\frac{0.200}{0.300}$

pH = 9.07