What is the ph of an 800ml solution prepared from 25g of KOH and water?

To find the pH of the solution, first calculate the concentration of KOH. KOH has a molar mass of approximately 56.11 g/mol, so 25 g of KOH is about 0.445 moles. In 800 mL (or 0.8 L) of solution, the concentration of KOH is 0.445 moles / 0.8 L = 0.556 M. Since KOH is a strong base and fully dissociates in water, the pOH is -log(0.556) ≈ 0.255, leading to a pH of 14 - 0.255 = 13.745. Therefore, the pH of the solution is approximately 13.75.