Calculate the pH of a solution formed by mixing 300.0 mL of 0.30 MHClO with 150.0 mL of 0.20 MLiClO. The Ka for HClO is 2.9*10-8.

pH = 7.06

Explanation:

The solution formed will be a buffer solution, which is a solution that contains a weak acid-base conjugate pair. The Henderson-Hasselbalch equation may be used to calculate the pH of a buffer solution, where A⁻ is the conjugate base (in this case, ClO⁻) and HA is the conjugate acid (in this case, HClO):

pH = pKa + log ([A⁻]/[HA]) = - log (Ka) + log ([A⁻]/[HA])

The concentration of the ClO⁻ in the final solution can be calculated using the dilution equation. The volume of the final solution is 450.0 mL.

C₂ = (C₁V₁) / V₂ = (0.20M) (150.0mL) / 450.0mL = 0.066 ... M

Similarly, the concentration of HClO in the final solution is:

C₂ = (C₁V₁) / V₂ = (0.30M) (300.0mL) / 450.0mL = 0.20 M

Substituting these values into the Henderson-Hasselbalch equation gives:

pH = - log (Ka) + log ([A⁻]/[HA]) = - log (2.9 x 10⁻⁸) + log (0.066 ... / 0.2) = 7.06