Calculate the pH of a 0.80 M HOCN solution that is 5.00% ionized.

Question

Quizplus · Accepted Answer

The correct answer is A because the pH of a 0.80 M HOCN solution that is 5.00% ionized is 1.40. This can be calculated using the Henderson-Hasselbalch equation: pH = pKa + log([A-]/[HA]), where pKa is the acid dissociation constant, [A-] is the concentration of the conjugate base, and [HA] is the concentration of the acid. The pKa of HOCN is 3.52, so the pH of a 0.80 M HOCN solution that is 5.00% ionized is 1.40.

Calculate the PH of a 0