1. Calculate the moles of KOH:

* Molar mass of KOH: 39.10 g/mol (K) + 16.00 g/mol (O) + 1.01 g/mol (H) = 56.11 g/mol

* Moles of KOH: (0.140 g KOH) / (56.11 g/mol) = 0.00250 mol KOH

2. Calculate the concentration of KOH:

* Concentration (Molarity): (0.00250 mol KOH) / (0.250 L solution) = 0.0100 M KOH

3. Understand the dissociation of KOH:

* KOH is a strong base, meaning it completely dissociates in water:

KOH(aq) → K+(aq) + OH-(aq)

* This means the concentration of OH- ions is equal to the concentration of KOH.

4. Calculate the pOH:

* pOH: -log[OH-] = -log(0.0100) = 2.00

5. Calculate the pH:

* pH + pOH = 14

* pH = 14 - pOH = 14 - 2.00 = 12.00

Therefore, the pH of the solution is 12.00.